diff --git a/la_chariotte/order/models.py b/la_chariotte/order/models.py
index a2e30b3..b6f446d 100644
--- a/la_chariotte/order/models.py
+++ b/la_chariotte/order/models.py
@@ -1,4 +1,5 @@
 from django.contrib.auth.models import User
+from django.core.exceptions import ValidationError
 from django.db import models
 from django.urls import reverse
 from django.utils import timezone
@@ -25,6 +26,16 @@ class GroupedOrder(models.Model):
     def get_absolute_url(self):
         return reverse("order:manage_items", kwargs={"pk": self.pk})
 
+    def clean_fields(self, exclude=None):
+        super().clean_fields(exclude=exclude)
+        if self.delivery_date < timezone.now().date():
+            raise ValidationError("La date de livraison ne doit pas être dans le passé")
+
+        if self.delivery_date < self.deadline.date():
+            raise ValidationError(
+                "La date limite de commande doit être avant la date de livraison"
+            )
+
     def __str__(self):  # pragma: no cover
         return (
             self.name
diff --git a/la_chariotte/order/tests/test_models.py b/la_chariotte/order/tests/test_models.py
index ed8612f..47ef195 100644
--- a/la_chariotte/order/tests/test_models.py
+++ b/la_chariotte/order/tests/test_models.py
@@ -1,11 +1,12 @@
 import datetime
 
+from django.urls import reverse
 from django.utils import timezone
 
 from la_chariotte.order.models import GroupedOrder
 
 
-class TestGroupedOrdersModel:
+class TestGroupedOrderModel:
     """Tests for Grouped orders model"""
 
     def test_is_ongoing_with_ongoing_grouped_order(self):
@@ -49,3 +50,63 @@ class TestGroupedOrdersModel:
         del_date = timezone.now().date() + datetime.timedelta(days=1)
         old_gr_order = GroupedOrder(deadline=deadline, delivery_date=del_date)
         assert old_gr_order.is_to_be_delivered()
+
+    def test_deadline_after_delivery_date(self, client_log):
+        """If the deadline is set after the delivery date, an validation error is raised"""
+        assert GroupedOrder.objects.count() == 0
+        create_gorder_url = reverse("order:create_grouped_order")
+        response = client_log.get(create_gorder_url)
+        assert response.status_code == 200
+        date = timezone.now().date() + datetime.timedelta(days=22)
+        deadline = timezone.now() + datetime.timedelta(days=32)
+        response = client_log.post(
+            create_gorder_url,
+            {"name": "titre test", "deadline": deadline, "delivery_date": date},
+        )
+        assert response.status_code == 200
+        assert not response.context.get("form").is_valid()
+        "La date limite de commande doit être avant la date de livraison" in response.content.decode()
+        assert (
+            response.context.get("form").errors["__all__"][0]
+            == "La date limite de commande doit être avant la date de livraison"
+        )
+        assert GroupedOrder.objects.count() == 0
+
+    def test_deadline_same_day_as_delivery_date(self, client_log):
+        """If the deadline is set the seame day as delivery date, no validation error is raised"""
+        assert GroupedOrder.objects.count() == 0
+        create_gorder_url = reverse("order:create_grouped_order")
+        response = client_log.get(create_gorder_url)
+        assert response.status_code == 200
+        date = timezone.now().date() + datetime.timedelta(days=32)
+        deadline = timezone.now() + datetime.timedelta(days=32)
+        response = client_log.post(
+            create_gorder_url,
+            {"name": "titre test", "deadline": deadline, "delivery_date": date},
+        )
+        assert response.status_code == 302
+        assert GroupedOrder.objects.count() == 1
+
+    def test_delivery_date_in_past(self, client_log):
+        """If the delivery date is set into the past, a validation error is raised"""
+        assert GroupedOrder.objects.count() == 0
+        create_gorder_url = reverse("order:create_grouped_order")
+        response = client_log.get(create_gorder_url)
+        assert response.status_code == 200
+        date = timezone.now().date() - datetime.timedelta(days=1)
+        deadline = timezone.now() - datetime.timedelta(days=3)
+        response = client_log.post(
+            create_gorder_url,
+            {"name": "titre test", "deadline": deadline, "delivery_date": date},
+        )
+        assert response.status_code == 200
+        assert not response.context.get("form").is_valid()
+        assert (
+            response.context.get("form").errors["__all__"][0]
+            == "La date de livraison ne doit pas être dans le passé"
+        )
+        "La date de livraison ne doit pas être dans le passé" in response.content.decode()
+        assert GroupedOrder.objects.count() == 0
+
+    def test_delivery_date_and_name_unique_together(self):
+        pass
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