diff --git a/CHANGELOG.md b/CHANGELOG.md
index 702e9427f5..ecb69d991d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,7 @@
 - Fix some search parameters validation [#1601](https://github.com/opendatateam/udata/pull/1601)
 - Prevent API tracking errors with unicode [#1602](https://github.com/opendatateam/udata/pull/1602)
 - Prevent a race condition error when uploading file with concurrent chunking [#1606](https://github.com/opendatateam/udata/pull/1606)
+- Disallow resources dict in API [#1603](https://github.com/opendatateam/udata/pull/1603)
 
 ## 1.3.6 (2018-04-16)
 
diff --git a/udata/forms/fields.py b/udata/forms/fields.py
index a16776d363..3358732ce4 100644
--- a/udata/forms/fields.py
+++ b/udata/forms/fields.py
@@ -475,9 +475,11 @@ def __init__(self, model_form, *args, **kwargs):
     def process(self, formdata, data=unset_value):
         self._formdata = formdata
         self.initial_data = data
-        self.has_data = formdata and any(
+        self.is_list_data = formdata and self.name in formdata
+        self.is_dict_data = formdata and any(
             k.startswith(self.prefix) for k in formdata
         )
+        self.has_data = self.is_list_data or self.is_dict_data
         if self.has_data:
             super(NestedModelList, self).process(formdata, data)
         else:
@@ -486,9 +488,11 @@ def process(self, formdata, data=unset_value):
 
     def validate(self, form, extra_validators=tuple()):
         '''Perform validation only if data has been submitted'''
-        # Run normal validation only if there is data for this form
         if not self.has_data:
             return True
+        if self.is_list_data:
+            if not isinstance(self._formdata[self.name], (list, tuple)):
+                return False
         return super(NestedModelList, self).validate(form, extra_validators)
 
     def populate_obj(self, obj, name):
diff --git a/udata/tests/api/test_datasets_api.py b/udata/tests/api/test_datasets_api.py
index 08e1e9c862..3fda2bd470 100644
--- a/udata/tests/api/test_datasets_api.py
+++ b/udata/tests/api/test_datasets_api.py
@@ -245,6 +245,20 @@ def test_dataset_api_create_with_resources(self):
         dataset = Dataset.objects.first()
         self.assertEqual(len(dataset.resources), 3)
 
+    def test_dataset_api_create_with_resources_dict(self):
+        """Create a dataset w/ resources in a dict instead of list,
+        should fail
+        """
+        data = DatasetFactory.as_dict()
+        data['resources'] = {
+            k: v for k, v in enumerate([
+                ResourceFactory.as_dict() for _ in range(3)
+            ])
+        }
+        with self.api_user():
+            response = self.post(url_for('api.datasets'), data)
+        self.assert400(response)
+
     def test_dataset_api_create_with_geom(self):
         '''It should create a dataset with resources from the API'''
         data = DatasetFactory.as_dict()