diff --git a/kfet/models.py b/kfet/models.py
index afbbe142..719a3b0d 100644
--- a/kfet/models.py
+++ b/kfet/models.py
@@ -152,7 +152,7 @@ class Account(models.Model):
 
     @property
     def readable(self):
-        return self.trigramme != "GNR"
+        return self.trigramme not in [KFET_DELETED_TRIGRAMME, KFET_GENERIC_TRIGRAMME]
 
     @property
     def is_team(self):
diff --git a/kfet/views.py b/kfet/views.py
index eb058eb4..f0cb796c 100644
--- a/kfet/views.py
+++ b/kfet/views.py
@@ -24,7 +24,7 @@ from django.views.generic.detail import BaseDetailView
 from django.views.generic.edit import CreateView, DeleteView, UpdateView
 
 from gestioncof.models import CofProfile
-from kfet import consumers
+from kfet import KFET_DELETED_TRIGRAMME, consumers
 from kfet.config import kfet_config
 from kfet.decorators import teamkfet_required
 from kfet.forms import (
@@ -79,6 +79,7 @@ from kfet.models import (
 )
 from kfet.statistic import ScaleMixin, WeekScale, last_stats_manifest
 
+from .auth import KFET_GENERIC_TRIGRAMME
 from .auth.views import (  # noqa
     AccountGroupCreate,
     AccountGroupUpdate,
@@ -492,6 +493,15 @@ class AccountDeleteView(PermissionRequiredMixin, DeleteView):
             )
             return redirect("kfet.account.read", self.object.trigramme)
 
+        if self.object.trigramme in [
+            "LIQ",
+            KFET_GENERIC_TRIGRAMME,
+            KFET_DELETED_TRIGRAMME,
+            "#13",
+        ]:
+            messages.error(request, "Impossible de supprimer un trigramme protégé !")
+            return redirect("kfet.account.read", self.object.trigramme)
+
         # SuccessMessageMixin does not work with DeleteView, see :
         # https://code.djangoproject.com/ticket/21926
         messages.success(request, self.success_message)