diff --git a/CHANGELOG.txt b/CHANGELOG.txt
index 3717d8672..004e4b2cb 100644
--- a/CHANGELOG.txt
+++ b/CHANGELOG.txt
@@ -12,6 +12,7 @@ Changelog
 
  * Fix: Added missing jQuery UI sprite files, causing collectstatic to throw errors (most reported on Heroku)
  * Fix: Page system check for on_delete actions of ForeignKeys was throwing false positives when page class decends from an abstract class (Alejandro Giacometti)
+ * Fix: Page system check for on_delete actions of ForeignKeys now only raises warnings, not errors
  * Fixed a regression where form builder submissions containing a number field would fail with a JSON serialisation error
  * Fix: Resizing an image with a focal point equal to the image size would result in a divide-by-zero error
  * Fix: Elasticsearch configuration now supports specifying HTTP authentication parameters as part of the URL, and defaults to ports 80 (HTTP) and 443 (HTTPS) if port number not specified
diff --git a/docs/releases/0.8.2.rst b/docs/releases/0.8.2.rst
index 41f980ed5..20072c7ee 100644
--- a/docs/releases/0.8.2.rst
+++ b/docs/releases/0.8.2.rst
@@ -16,6 +16,7 @@ Bug fixes
 
  * Added missing jQuery UI sprite files, causing collectstatic to throw errors (most reported on Heroku)
  * Page system check for on_delete actions of ForeignKeys was throwing false positives when page class decends from an abstract class (Alejandro Giacometti)
+ * Page system check for on_delete actions of ForeignKeys now only raises warnings, not errors
  * Fixed a regression where form builder submissions containing a number field would fail with a JSON serialisation error
  * Resizing an image with a focal point equal to the image size would result in a divide-by-zero error
  * Elasticsearch configuration now supports specifying HTTP authentication parameters as part of the URL, and defaults to ports 80 (HTTP) and 443 (HTTPS) if port number not specified
diff --git a/wagtail/wagtailcore/models.py b/wagtail/wagtailcore/models.py
index 4d27f6e53..47b9305c4 100644
--- a/wagtail/wagtailcore/models.py
+++ b/wagtail/wagtailcore/models.py
@@ -385,11 +385,11 @@ class Page(six.with_metaclass(PageBase, MP_Node, ClusterableModel, index.Indexed
             if isinstance(field, models.ForeignKey) and field.name not in field_exceptions:
                 if field.rel.on_delete == models.CASCADE:
                     errors.append(
-                        checks.Error(
+                        checks.Warning(
                             "Field hasn't specified on_delete action",
                             hint="Set on_delete=models.SET_NULL and make sure the field is nullable.",
                             obj=field,
-                            id='wagtailcore.E001',
+                            id='wagtailcore.W001',
                         )
                     )