diff --git a/app/models/prefill_description.rb b/app/models/prefill_description.rb
index 2148b3dce..090e02fb8 100644
--- a/app/models/prefill_description.rb
+++ b/app/models/prefill_description.rb
@@ -45,15 +45,33 @@ class PrefillDescription < SimpleDelegator
 
   private
 
-  def prefilled_champs_for_link
-    prefilled_champs.map { |type_de_champ| ["champ_#{type_de_champ.to_typed_id}", type_de_champ.example_value] }.to_h
-  end
-
-  def prefilled_champs_for_query
-    prefilled_champs.map { |type_de_champ| "\"champ_#{type_de_champ.to_typed_id}\": \"#{type_de_champ.example_value}\"" } .join(', ')
-  end
-
   def active_fillable_public_types_de_champ
     active_revision.types_de_champ_public.fillable
   end
+
+  def prefilled_champs_for_link
+    prefilled_champs_as_params.map(&:to_a).to_h
+  end
+
+  def prefilled_champs_for_query
+    prefilled_champs_as_params.map(&:to_s).join(', ')
+  end
+
+  def prefilled_champs_as_params
+    prefilled_champs.map { |type_de_champ| Param.new(type_de_champ.to_typed_id, type_de_champ.example_value) }
+  end
+
+  Param = Struct.new(:key, :value) do
+    def to_a
+      ["champ_#{key}", value]
+    end
+
+    def to_s
+      if value.is_a?(Array)
+        "\"champ_#{key}\": #{value}"
+      else
+        "\"champ_#{key}\": \"#{value}\""
+      end
+    end
+  end
 end
diff --git a/spec/models/prefill_description_spec.rb b/spec/models/prefill_description_spec.rb
index 65c8cd1a5..5c5846965 100644
--- a/spec/models/prefill_description_spec.rb
+++ b/spec/models/prefill_description_spec.rb
@@ -101,6 +101,19 @@ RSpec.describe PrefillDescription, type: :model do
         )
       )
     end
+
+    context 'when the type de champ can have multiple values' do
+      let(:type_de_champ) { create(:type_de_champ_multiple_drop_down_list, procedure: procedure) }
+
+      it 'builds the URL with array parameter' do
+        expect(prefill_description.prefill_link).to eq(
+          commencer_url(
+            path: procedure.path,
+            "champ_#{type_de_champ.to_typed_id}": TypesDeChamp::PrefillMultipleDropDownListTypeDeChamp.new(type_de_champ).example_value
+          )
+        )
+      end
+    end
   end
 
   describe '#prefill_query' do
@@ -120,5 +133,20 @@ RSpec.describe PrefillDescription, type: :model do
     it "builds the query to create a new prefilled dossier" do
       expect(prefill_description.prefill_query).to eq(expected_query)
     end
+
+    context 'when the type de champ can have multiple values' do
+      let(:type_de_champ) { create(:type_de_champ_multiple_drop_down_list, procedure: procedure) }
+      let(:expected_query) do
+        <<~TEXT
+          curl --request POST '#{api_public_v1_dossiers_url(procedure)}' \\
+               --header 'Content-Type: application/json' \\
+               --data '{"champ_#{type_de_champ.to_typed_id}": #{TypesDeChamp::PrefillMultipleDropDownListTypeDeChamp.new(type_de_champ).example_value}}'
+        TEXT
+      end
+
+      it 'builds the query with array parameter' do
+        expect(prefill_description.prefill_query).to eq(expected_query)
+      end
+    end
   end
 end