diff --git a/app/components/attachment/edit_component.rb b/app/components/attachment/edit_component.rb
index 38a98bda3..25ec4e2ea 100644
--- a/app/components/attachment/edit_component.rb
+++ b/app/components/attachment/edit_component.rb
@@ -1,16 +1,27 @@
 # Display a widget for uploading, editing and deleting a file attachment
 class Attachment::EditComponent < ApplicationComponent
-  def initialize(form:, attached_file:, template: nil, user_can_destroy: false, direct_upload: true, id: nil)
+  attr_reader :template, :form, :attachment
+
+  delegate :persisted?, to: :attachment, allow_nil: true
+
+  def initialize(form:, attached_file:, attachment: nil, user_can_destroy: false, direct_upload: true, id: nil, index: 0)
     @form = form
     @attached_file = attached_file
-    @template = template
+
+    @attachment = if attachment
+      attachment
+    elsif attached_file.respond_to?(:attachment)
+      attached_file.attachment
+    else
+      # multiple attachments: attachment kwarg is expected, unless adding a new attachment
+    end
+
     @user_can_destroy = user_can_destroy
     @direct_upload = direct_upload
     @id = id
+    @index = index
   end
 
-  attr_reader :template, :form
-
   def max_file_size
     file_size_validator.options[:less_than]
   end
@@ -19,26 +30,18 @@ class Attachment::EditComponent < ApplicationComponent
     @user_can_destroy
   end
 
-  def attachment
-    @attached_file.attachment
-  end
-
   def attachment_path
     helpers.attachment_path attachment.id, { signed_id: attachment.blob.signed_id }
   end
 
   def attachment_id
-    @attachment_id ||= attachment ? attachment.id : SecureRandom.uuid
+    @attachment_id ||= (attachment&.id || SecureRandom.uuid)
   end
 
   def attachment_input_class
     "attachment-input-#{attachment_id}"
   end
 
-  def persisted?
-    attachment&.persisted?
-  end
-
   def champ
     @form.object.is_a?(Champ) ? @form.object : nil
   end
@@ -51,13 +54,25 @@ class Attachment::EditComponent < ApplicationComponent
       id: input_id(@id),
       aria: { describedby: champ&.describedby_id },
       data: {
-        auto_attach_url: helpers.auto_attach_url(form.object)
-      }.merge(has_file_size_validator? ? { max_file_size: max_file_size } : {})
+        auto_attach_url:
+      }.merge(has_file_size_validator? ? { max_file_size: } : {})
     }.merge(has_content_type_validator? ? { accept: accept_content_type } : {})
   end
 
+  def auto_attach_url
+    helpers.auto_attach_url(form.object, replace_attachment_id: persisted? ? attachment_id : nil)
+  end
+
   def input_id(given_id)
-    [given_id, champ&.input_id, file_field_name].reject(&:blank?).compact.first
+    return given_id if given_id.present?
+
+    if champ.present?
+      # Single or first attachment input must match label "for" attribute. Others must remain unique.
+      return champ.input_id if @index.zero?
+      return "#{champ.input_id}_#{attachment_id}"
+    end
+
+    file_field_name
   end
 
   def file_field_name
diff --git a/app/components/attachment/edit_component/edit_component.html.haml b/app/components/attachment/edit_component/edit_component.html.haml
index 42520586d..fc3e60515 100644
--- a/app/components/attachment/edit_component/edit_component.html.haml
+++ b/app/components/attachment/edit_component/edit_component.html.haml
@@ -1,15 +1,4 @@
-.attachment
-  - if template&.attached?
-    %p.mb-1
-      Veuillez télécharger, remplir et joindre
-      = link_to(url_for(template), download: "", class: "fr-link fr-link--icon-right fr-icon-download-line") do
-        le modèle suivant
-
-      - if helpers.administrateur_signed_in?
-        %span.ml-2.fr-text--xs.fr-text-mention--grey.visible-on-previous-hover
-          %span.fr-text-action-high--blue-france.fr-icon-questionnaire-line{ "aria-hidden": "true" }
-          = t('shared.ephemeral_link')
-
+.fr-mb-2w
   - if persisted?
     .attachment-actions{ id: dom_id(attachment, :actions) }
       .attachment-action
@@ -30,8 +19,9 @@
       %span.icon.retry
       Ré-essayer
 
+  - if !persisted?
+    %label.text-sm.font-weight-normal{ for: file_field_options[:id] }
+      = t('.max_file_size', max_file_size: number_to_human_size(max_file_size))
 
-  %label.text-sm.font-weight-normal{ for: file_field_options[:id] }
-    = t('.max_file_size', max_file_size: number_to_human_size(max_file_size))
+  %p= form.file_field(file_field_name, **file_field_options)
 
-  = form.file_field(file_field_name, **file_field_options)
diff --git a/app/components/attachment/multiple_component.rb b/app/components/attachment/multiple_component.rb
new file mode 100644
index 000000000..fe9f42135
--- /dev/null
+++ b/app/components/attachment/multiple_component.rb
@@ -0,0 +1,43 @@
+# Display a widget for uploading, editing and deleting a file attachment
+class Attachment::MultipleComponent < ApplicationComponent
+  renders_one :template
+
+  attr_reader :form
+  attr_reader :attached_file
+  attr_reader :direct_upload
+  attr_reader :id
+  attr_reader :user_can_destroy
+
+  delegate :count, :empty?, to: :attachments, prefix: true
+
+  def initialize(form:, attached_file:, user_can_destroy: false, direct_upload: true, id: nil)
+    @form = form
+    @attached_file = attached_file
+    @user_can_destroy = user_can_destroy
+    @direct_upload = direct_upload
+    @id = id
+
+    @attachments = attached_file.attachments || []
+  end
+
+  def each_attachment(&block)
+    @attachments.each_with_index(&block)
+  end
+
+  def can_attach_next?
+    return false if @attachments.empty?
+    return false if !@attachments.last.persisted?
+
+    true
+  end
+
+  def stimulus_controller_name
+    "attachment-multiple"
+  end
+
+  private
+
+  def attachments
+    @attachments
+  end
+end
diff --git a/app/components/attachment/multiple_component/multiple_component.html.haml b/app/components/attachment/multiple_component/multiple_component.html.haml
new file mode 100644
index 000000000..53a8b76b6
--- /dev/null
+++ b/app/components/attachment/multiple_component/multiple_component.html.haml
@@ -0,0 +1,13 @@
+.fr-mb-4w{ data: { controller: stimulus_controller_name }}
+  = template
+
+  - each_attachment do |attachment, index|
+    %div{id: dom_id(attachment)}
+      = render Attachment::EditComponent.new(form:, attached_file:, attachment:, user_can_destroy:, direct_upload:, id:, index:)
+
+  %div{class: [attachments_empty? ? nil : "hidden"], data: { "#{stimulus_controller_name}-target": "empty" }}
+    = render Attachment::EditComponent.new(form:, attached_file:, user_can_destroy:, direct_upload:, id:, index: attachments_count)
+
+  - if can_attach_next?
+    %button.fr-btn.fr-btn--tertiary.fr-btn--sm{ data: { "#{stimulus_controller_name}-target": "buttonAdd", action: "click->attachment-multiple#add" }} Ajouter un fichier
+
diff --git a/app/components/editable_champ/piece_justificative_component/piece_justificative_component.html.haml b/app/components/editable_champ/piece_justificative_component/piece_justificative_component.html.haml
index 9ad12d070..9805b2050 100644
--- a/app/components/editable_champ/piece_justificative_component/piece_justificative_component.html.haml
+++ b/app/components/editable_champ/piece_justificative_component/piece_justificative_component.html.haml
@@ -1,2 +1,14 @@
 - user_can_destroy = !@champ.mandatory? || @champ.dossier.brouillon?
-= render Attachment::EditComponent.new(form: @form, attached_file: @champ.piece_justificative_file, template: @champ.type_de_champ.piece_justificative_template, user_can_destroy: user_can_destroy)
+= render Attachment::MultipleComponent.new(form: @form, attached_file: @champ.piece_justificative_file, user_can_destroy: user_can_destroy) do |c|
+  - if @champ.type_de_champ.piece_justificative_template&.attached?
+    - c.with_template do
+      %p
+        Veuillez télécharger, remplir et joindre
+        = link_to(url_for(@champ.type_de_champ.piece_justificative_template), download: "", class: "fr-link fr-link--icon-right fr-icon-download-line") do
+          le modèle suivant
+
+        - if helpers.administrateur_signed_in?
+          %span.fr-ml-2w.fr-text--xs.fr-text-mention--grey.visible-on-previous-hover
+            %span.fr-text-action-high--blue-france.fr-icon-questionnaire-line{ "aria-hidden": "true" }
+            = t('shared.ephemeral_link')
+
diff --git a/app/controllers/champs/piece_justificative_controller.rb b/app/controllers/champs/piece_justificative_controller.rb
index 1eed530b8..807bb70d2 100644
--- a/app/controllers/champs/piece_justificative_controller.rb
+++ b/app/controllers/champs/piece_justificative_controller.rb
@@ -13,6 +13,9 @@ class Champs::PieceJustificativeController < ApplicationController
 
   def attach_piece_justificative
     @champ = policy_scope(Champ).find(params[:champ_id])
+
+    purge_replaced_attachment
+
     @champ.piece_justificative_file.attach(params[:blob_signed_id])
     save_succeed = @champ.save
     @champ.dossier.update(last_champ_updated_at: Time.zone.now.utc) if save_succeed
@@ -24,4 +27,11 @@ class Champs::PieceJustificativeController < ApplicationController
   rescue ActiveRecord::StaleObjectError
     attach_piece_justificative
   end
+
+  def purge_replaced_attachment
+    return if params[:replace_attachment_id].blank?
+
+    attachment = @champ.piece_justificative_file.attachments.find { _1.id == params[:replace_attachment_id].to_i }
+    attachment&.purge_later
+  end
 end
diff --git a/app/helpers/champ_helper.rb b/app/helpers/champ_helper.rb
index 2a66461bf..d57caaf8b 100644
--- a/app/helpers/champ_helper.rb
+++ b/app/helpers/champ_helper.rb
@@ -7,9 +7,9 @@ module ChampHelper
     simple_format(auto_linked_text, {}, sanitize: false)
   end
 
-  def auto_attach_url(object)
+  def auto_attach_url(object, url_options = {})
     if object.is_a?(Champ)
-      champs_piece_justificative_url(object.id)
+      champs_piece_justificative_url(object.id, url_options)
     elsif object.is_a?(TypeDeChamp)
       piece_justificative_template_admin_procedure_type_de_champ_url(stable_id: object.stable_id, procedure_id: object.procedure.id)
     end
diff --git a/app/javascript/controllers/attachment_multiple_controller.ts b/app/javascript/controllers/attachment_multiple_controller.ts
new file mode 100644
index 000000000..a71bed991
--- /dev/null
+++ b/app/javascript/controllers/attachment_multiple_controller.ts
@@ -0,0 +1,50 @@
+import {} from '@hotwired/stimulus';
+import { show, hide } from '~/shared/utils';
+import { ApplicationController } from './application_controller';
+
+type AttachementDestroyedEvent = CustomEvent<{ target_id: string }>;
+
+export class AttachmentMultipleController extends ApplicationController {
+  static targets = ['buttonAdd', 'empty'];
+
+  declare readonly emptyTarget: HTMLDivElement;
+  declare readonly buttonAddTarget: HTMLButtonElement;
+
+  connect() {
+    this.onGlobal('attachment:destroyed', (event: AttachementDestroyedEvent) =>
+      this.onAttachmentDestroy(event)
+    );
+  }
+
+  add(event: Event) {
+    event.preventDefault();
+
+    hide(this.buttonAddTarget);
+
+    show(this.emptyTarget);
+
+    const inputFile = this.emptyTarget.querySelector(
+      'input[type=file]'
+    ) as HTMLInputElement;
+
+    inputFile.click();
+  }
+
+  onAttachmentDestroy(event: AttachementDestroyedEvent) {
+    const { detail } = event;
+
+    const attachmentWrapper = document.getElementById(detail.target_id);
+
+    // Remove this attachment row when there is at least another attachment.
+    if (attachmentWrapper && this.attachmentsCount() > 1) {
+      attachmentWrapper.parentNode?.removeChild(attachmentWrapper);
+    } else {
+      hide(this.buttonAddTarget);
+    }
+  }
+
+  attachmentsCount() {
+    // Don't count the hidden "empty" attachment
+    return this.element.querySelectorAll('.attachment-input').length - 1;
+  }
+}
diff --git a/app/models/champs/piece_justificative_champ.rb b/app/models/champs/piece_justificative_champ.rb
index dfde878e5..708f17d24 100644
--- a/app/models/champs/piece_justificative_champ.rb
+++ b/app/models/champs/piece_justificative_champ.rb
@@ -43,12 +43,16 @@ class Champs::PieceJustificativeChamp < Champ
   end
 
   def for_export
-    piece_justificative_file.filename.to_s if piece_justificative_file.attached?
+    piece_justificative_file.map { _1.filename.to_s }
   end
 
   def for_api
-    if piece_justificative_file.attached? && (piece_justificative_file.virus_scanner.safe? || piece_justificative_file.virus_scanner.pending?)
-      piece_justificative_file.service_url
+    return nil unless piece_justificative_file.attached?
+
+    piece_justificative_file.filter_map do |attachment|
+      if attachment.virus_scanner.safe? || attachment.virus_scanner.pending?
+        attachment.service_url
+      end
     end
   end
 end
diff --git a/app/views/attachments/destroy.turbo_stream.haml b/app/views/attachments/destroy.turbo_stream.haml
index 323dd8f03..3d4600326 100644
--- a/app/views/attachments/destroy.turbo_stream.haml
+++ b/app/views/attachments/destroy.turbo_stream.haml
@@ -1,2 +1,3 @@
 = turbo_stream.remove dom_id(@attachment, :actions)
+= turbo_stream.dispatch "attachment:destroyed", { target_id: dom_id(@attachment) }
 = turbo_stream.show_all ".attachment-input-#{@attachment.id}"
diff --git a/app/views/champs/piece_justificative/show.turbo_stream.haml b/app/views/champs/piece_justificative/show.turbo_stream.haml
index c170e5cb5..42c362406 100644
--- a/app/views/champs/piece_justificative/show.turbo_stream.haml
+++ b/app/views/champs/piece_justificative/show.turbo_stream.haml
@@ -2,6 +2,6 @@
   = turbo_stream.morph @champ.input_group_id do
     = render EditableChamp::EditableChampComponent.new champ: @champ, form: form
 
-- if @champ.piece_justificative_file.attached?
-  - attachment = @champ.piece_justificative_file.attachment
+
+- @champ.piece_justificative_file.attachments.each do |attachment|
   = turbo_stream.focus_all "button[data-toggle-target=\".attachment-input-#{attachment.id}\"]"
diff --git a/spec/components/editable_champ/piece_justificative_component/piece_justificative_component_spec.rb b/spec/components/editable_champ/piece_justificative_component/piece_justificative_component_spec.rb
new file mode 100644
index 000000000..705984960
--- /dev/null
+++ b/spec/components/editable_champ/piece_justificative_component/piece_justificative_component_spec.rb
@@ -0,0 +1,32 @@
+describe EditableChamp::PieceJustificativeComponent, type: :component do
+  let(:champ) { build(:champ_piece_justificative, dossier: create(:dossier)) }
+  let(:component) {
+    described_class.new(form: instance_double(ActionView::Helpers::FormBuilder, object: champ.dossier, file_field: "<input type=\"file\" />"), champ:)
+  }
+
+  let(:subject) {
+    render_inline(component).to_html
+  }
+
+  context 'when there is a template' do
+    let(:template) { champ.type_de_champ.piece_justificative_template }
+    let(:profil) { :user }
+
+    before do
+      allow_any_instance_of(ApplicationController).to receive(:administrateur_signed_in?).and_return(profil == :administrateur)
+    end
+
+    it 'renders a link to template' do
+      expect(subject).to have_link('le modèle suivant')
+      expect(subject).not_to have_text("éphémère")
+    end
+
+    context 'as an administrator' do
+      let(:profil) { :administrateur }
+      it 'warn about ephemeral template url' do
+        expect(subject).to have_link('le modèle suivant')
+        expect(subject).to have_text("éphémère")
+      end
+    end
+  end
+end
diff --git a/spec/factories/champ.rb b/spec/factories/champ.rb
index d531fd980..a52f096f8 100644
--- a/spec/factories/champ.rb
+++ b/spec/factories/champ.rb
@@ -162,8 +162,13 @@ FactoryBot.define do
 
     factory :champ_titre_identite, class: 'Champs::TitreIdentiteChamp' do
       type_de_champ { association :type_de_champ_titre_identite, procedure: dossier.procedure }
+      transient do
+        skip_default_attachment { false }
+      end
+
+      after(:build) do |champ, evaluator|
+        next if evaluator.skip_default_attachment
 
-      after(:build) do |champ, _evaluator|
         champ.piece_justificative_file.attach(
           io: StringIO.new("toto"),
           filename: "toto.png",
diff --git a/spec/models/champ_spec.rb b/spec/models/champ_spec.rb
index a5f3641d8..6ef81bde5 100644
--- a/spec/models/champ_spec.rb
+++ b/spec/models/champ_spec.rb
@@ -452,13 +452,13 @@ describe Champ do
         end
 
         it 'marks the file as pending virus scan' do
-          expect(subject.piece_justificative_file.virus_scanner.started?).to be_truthy
+          expect(subject.piece_justificative_file.first.virus_scanner.started?).to be_truthy
         end
 
         it 'marks the file as safe once the scan completes' do
           subject
           perform_enqueued_jobs
-          expect(champ.reload.piece_justificative_file.virus_scanner.safe?).to be_truthy
+          expect(champ.reload.piece_justificative_file.first.virus_scanner.safe?).to be_truthy
         end
       end
     end
@@ -467,7 +467,7 @@ describe Champ do
   describe '#enqueue_watermark_job' do
     context 'when type_champ is type_de_champ_titre_identite' do
       let(:type_de_champ) { create(:type_de_champ_titre_identite) }
-      let(:champ) { build(:champ_titre_identite, type_de_champ: type_de_champ) }
+      let(:champ) { build(:champ_titre_identite, type_de_champ: type_de_champ, skip_default_attachment: true) }
 
       before do
         allow(ClamavService).to receive(:safe_file?).and_return(true)
@@ -480,14 +480,14 @@ describe Champ do
       end
 
       it 'marks the file as needing watermarking' do
-        expect(subject.piece_justificative_file.watermark_pending?).to be_truthy
+        expect(subject.piece_justificative_file.first.watermark_pending?).to be_truthy
       end
 
       it 'watermarks the file' do
         subject
         perform_enqueued_jobs
-        expect(champ.reload.piece_justificative_file.watermark_pending?).to be_falsy
-        expect(champ.reload.piece_justificative_file.blob.watermark_done?).to be_truthy
+        expect(champ.reload.piece_justificative_file.first.watermark_pending?).to be_falsy
+        expect(champ.reload.piece_justificative_file.first.blob.watermark_done?).to be_truthy
       end
     end
   end
diff --git a/spec/models/champs/piece_justificative_champ_spec.rb b/spec/models/champs/piece_justificative_champ_spec.rb
index 9d3d239b1..1e0c9c80c 100644
--- a/spec/models/champs/piece_justificative_champ_spec.rb
+++ b/spec/models/champs/piece_justificative_champ_spec.rb
@@ -43,35 +43,35 @@ describe Champs::PieceJustificativeChamp do
     let(:champ_pj) { create(:champ_piece_justificative) }
     subject { champ_pj.for_export }
 
-    it { is_expected.to eq('toto.txt') }
+    it { is_expected.to match_array(['toto.txt']) }
 
     context 'without attached file' do
       before { champ_pj.piece_justificative_file.purge }
-      it { is_expected.to eq(nil) }
+      it { is_expected.to eq([]) }
     end
   end
 
   describe '#for_api' do
     let(:champ_pj) { create(:champ_piece_justificative) }
-    let(:metadata) { champ_pj.piece_justificative_file.blob.metadata }
+    let(:metadata) { champ_pj.piece_justificative_file.first.blob.metadata }
 
-    before { champ_pj.piece_justificative_file.blob.update(metadata: metadata.merge(virus_scan_result: status)) }
+    before { champ_pj.piece_justificative_file.first.blob.update(metadata: metadata.merge(virus_scan_result: status)) }
 
     subject { champ_pj.for_api }
 
     context 'when file is safe' do
       let(:status) { ActiveStorage::VirusScanner::SAFE }
-      it { is_expected.to include("/rails/active_storage/disk/") }
+      it { is_expected.to match_array([include("/rails/active_storage/disk/")]) }
     end
 
     context 'when file is not scanned' do
       let(:status) { ActiveStorage::VirusScanner::PENDING }
-      it { is_expected.to include("/rails/active_storage/disk/") }
+      it { is_expected.to match_array([include("/rails/active_storage/disk/")]) }
     end
 
     context 'when file is infected' do
       let(:status) { ActiveStorage::VirusScanner::INFECTED }
-      it { is_expected.to be_nil }
+      it { is_expected.to eq([]) }
     end
   end
 end
diff --git a/spec/services/pieces_justificatives_service_spec.rb b/spec/services/pieces_justificatives_service_spec.rb
index 882d6f035..fb58bcc54 100644
--- a/spec/services/pieces_justificatives_service_spec.rb
+++ b/spec/services/pieces_justificatives_service_spec.rb
@@ -20,7 +20,18 @@ describe PiecesJustificativesService do
         attach_file_to_champ(pj_champ.call(witness))
       end
 
-      it { expect(subject).to match_array([pj_champ.call(dossier).piece_justificative_file.attachment]) }
+      context 'with a single attachment' do
+        it { expect(subject).to match_array(pj_champ.call(dossier).piece_justificative_file.attachments) }
+      end
+
+      context 'with a multiple attachments' do
+        before do
+          attach_file_to_champ(pj_champ.call(dossier))
+        end
+
+        it { expect(subject.count).to eq(2) }
+        it { expect(subject).to match_array(pj_champ.call(dossier).piece_justificative_file.attachments) }
+      end
     end
 
     context 'with a pj not safe on a champ' do
@@ -46,7 +57,7 @@ describe PiecesJustificativesService do
         attach_file_to_champ(private_pj_champ.call(witness))
       end
 
-      it { expect(subject).to match_array([private_pj_champ.call(dossier).piece_justificative_file.attachment]) }
+      it { expect(subject).to match_array(private_pj_champ.call(dossier).piece_justificative_file.attachments) }
 
       context 'for expert' do
         let(:for_expert) { true }
diff --git a/spec/views/shared/attachment/_update.html.haml_spec.rb b/spec/views/shared/attachment/_update.html.haml_spec.rb
index 2f120f12d..10d689243 100644
--- a/spec/views/shared/attachment/_update.html.haml_spec.rb
+++ b/spec/views/shared/attachment/_update.html.haml_spec.rb
@@ -6,7 +6,7 @@ describe 'shared/attachment/_update.html.haml', type: :view do
 
   subject do
     form_for(champ.dossier) do |form|
-      view.render Attachment::EditComponent.new(form: form, attached_file: attached_file, user_can_destroy: true, direct_upload: true, template:)
+      view.render Attachment::EditComponent.new(form: form, attached_file: attached_file, user_can_destroy: true, direct_upload: true)
     end
   end
 
@@ -65,26 +65,4 @@ describe 'shared/attachment/_update.html.haml', type: :view do
       is_expected.not_to have_link('Supprimer')
     end
   end
-
-  context 'when champ has a template' do
-    let(:profil) { :user }
-    let(:template) { champ.type_de_champ.piece_justificative_template }
-
-    before do
-      allow_any_instance_of(ActionView::Base).to receive(:administrateur_signed_in?).and_return(profil == :administrateur)
-    end
-
-    it 'renders a link to template' do
-      expect(subject).to have_link('le modèle suivant')
-      expect(subject).not_to have_text("éphémère")
-    end
-
-    context 'as an administrator' do
-      let(:profil) { :administrateur }
-      it 'warn about ephemeral template url' do
-        expect(subject).to have_link('le modèle suivant')
-        expect(subject).to have_text("éphémère")
-      end
-    end
-  end
 end