diff --git a/passerelle/apps/atal/models.py b/passerelle/apps/atal/models.py
index 531b1157..908b4ba8 100644
--- a/passerelle/apps/atal/models.py
+++ b/passerelle/apps/atal/models.py
@@ -23,6 +23,7 @@ from django.db import models
 from django.utils import dateformat, dateparse
 from django.utils.translation import gettext_lazy as _
 from zeep import helpers
+from zeep.exceptions import Fault
 
 from passerelle.base.models import BaseResource
 from passerelle.utils.api import endpoint
@@ -286,7 +287,11 @@ class ATALConnector(BaseResource):
             'numeroDemande': post_data['numero_demande'],
             'nomFichier': filename,
         }
-        self._soap_call(wsdl='ChargementPiecesJointesService', method='upload', **data)
+        try:
+            self._soap_call(wsdl='ChargementPiecesJointesService', method='upload', **data)
+        except Fault as e:
+            raise APIError(str(e))
+
         return {}
 
     @endpoint(
diff --git a/tests/test_atal.py b/tests/test_atal.py
index 471f1739..adae3dcb 100644
--- a/tests/test_atal.py
+++ b/tests/test_atal.py
@@ -7,6 +7,7 @@ import pytest
 from django.contrib.contenttypes.models import ContentType
 from django.utils.http import urlencode
 from requests import RequestException
+from zeep.exceptions import Fault
 
 from passerelle.apps.atal.models import ATALConnector
 from passerelle.base.models import AccessRight, ApiUser
@@ -189,6 +190,15 @@ def test_upload(app, connector, monkeypatch):
     }
 
 
+def test_upload_file_too_big(app, connector, monkeypatch):
+    mock_atal_soap_call(monkeypatch, side_effect=Fault('File too big'))
+    base64_str = 'eyJsYXN0X2NoZWNrIjoiMjAxOS0wNC0xMFQxMjowODoyOVoiL' + 'CJweXBpX3ZlcnNpb24iOiIxOS4wLjMifQ=='
+    params = {'numero_demande': 'DIT19050001', 'nom_fichier': 'data.json', 'file': {'content': base64_str}}
+    response = app.post_json('/atal/slug-atal/upload', params=params)
+    assert response.json['err'] == 1
+    assert response.json['err_desc'] == 'File too big'
+
+
 def test_retrieve_details_demande(app, connector, monkeypatch):
     import passerelle.utils