diff --git a/CHANGELOG.md b/CHANGELOG.md
index fead883..8923781 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,10 @@
 - Add `AUDITLOG_USE_BASE_MANAGER` setting to override default manager use ([#766](https://github.com/jazzband/django-auditlog/pull/766))
 - Drop 'Python 3.9' support ([#773](https://github.com/jazzband/django-auditlog/pull/773))
 
+#### Fixes
+
+- Make diffing more robust for polymorphic models ([#784](https://github.com/jazzband/django-auditlog/pull/784))
+
 ## 3.3.0 (2025-09-18)
 
 #### Improvements
diff --git a/auditlog/diff.py b/auditlog/diff.py
index 0d69749..dd64d20 100644
--- a/auditlog/diff.py
+++ b/auditlog/diff.py
@@ -3,7 +3,7 @@ from collections.abc import Callable
 from datetime import timezone
 
 from django.conf import settings
-from django.core.exceptions import ObjectDoesNotExist
+from django.core.exceptions import FieldDoesNotExist, ObjectDoesNotExist
 from django.db.models import NOT_PROVIDED, DateTimeField, ForeignKey, JSONField, Model
 from django.utils import timezone as django_timezone
 from django.utils.encoding import smart_str
@@ -74,7 +74,7 @@ def get_field_value(obj, field, use_json_for_changes=False):
         try:
             model_field = obj._meta.get_field(field.name)
             default = model_field.default
-        except AttributeError:
+        except (AttributeError, FieldDoesNotExist):
             default = NOT_PROVIDED
 
         if default is NOT_PROVIDED:
diff --git a/auditlog_tests/test_app/models.py b/auditlog_tests/test_app/models.py
index e996a25..0ee7852 100644
--- a/auditlog_tests/test_app/models.py
+++ b/auditlog_tests/test_app/models.py
@@ -487,6 +487,7 @@ auditlog.register(AltPrimaryKeyModel)
 auditlog.register(UUIDPrimaryKeyModel)
 auditlog.register(ModelPrimaryKeyModel)
 auditlog.register(ProxyModel)
+auditlog.register(RelatedModelParent)
 auditlog.register(RelatedModel)
 auditlog.register(ManyRelatedModel)
 auditlog.register(ManyRelatedModel.recursive.through)
diff --git a/auditlog_tests/tests.py b/auditlog_tests/tests.py
index f12ef9d..b446880 100644
--- a/auditlog_tests/tests.py
+++ b/auditlog_tests/tests.py
@@ -47,6 +47,7 @@ from test_app.models import (
     NullableJSONModel,
     ProxyModel,
     RelatedModel,
+    RelatedModelParent,
     ReusableThroughRelatedModel,
     SecretM2MModel,
     SecretRelatedModel,
@@ -2131,6 +2132,27 @@ class ModelInstanceDiffTest(TestCase):
         model_instance_diff(simple2, simple1)
         model_instance_diff(simple1, simple2)
 
+    def test_diff_polymorphic_models(self):
+        """No error is raised when comparing parent/child for polymorphic models."""
+
+        # This tests that when a polymorphic model is compared to its parent,
+        # no FieldDoesNotExist errors are raised because those fields don't exist
+        # on the parent model.
+
+        # relation target
+        simple = SimpleModel()
+        simple.save()
+
+        # the parent model
+        related_parent = RelatedModelParent()
+        related_parent.save()
+
+        # the child model, with some fields that don't exist on the parent
+        related = RelatedModel(related=simple, one_to_one=simple)
+        related.save()
+
+        model_instance_diff(related, related_parent)
+
     def test_object_repr_related_deleted(self):
         """No error is raised when __str__() loads a related object that has been deleted."""
         simple = SimpleModel()