diff --git a/django/forms/models.py b/django/forms/models.py
index 8134cf3de3..414a9eafe4 100644
--- a/django/forms/models.py
+++ b/django/forms/models.py
@@ -1132,7 +1132,7 @@ class ModelChoiceIterator:
             yield ("", self.field.empty_label)
         queryset = self.queryset
         # Can't use iterator() when queryset uses prefetch_related()
-        if not queryset._prefetch_related_lookups:
+        if not queryset._prefetch_related_lookups and queryset._result_cache is None:
             queryset = queryset.iterator()
         for obj in queryset:
             yield self.choice(obj)
diff --git a/tests/model_forms/test_modelchoicefield.py b/tests/model_forms/test_modelchoicefield.py
index 6b0f00cf7f..733175823f 100644
--- a/tests/model_forms/test_modelchoicefield.py
+++ b/tests/model_forms/test_modelchoicefield.py
@@ -257,6 +257,17 @@ class ModelChoiceFieldTests(TestCase):
             (self.c3.pk, 'Third'),
         ])
 
+    def test_queryset_result_cache_is_reused(self):
+        f = forms.ModelChoiceField(Category.objects.all())
+        with self.assertNumQueries(1):
+            # list() calls __len__() and __iter__(); no duplicate queries.
+            self.assertEqual(list(f.choices), [
+                ('', '---------'),
+                (self.c1.pk, 'Entertainment'),
+                (self.c2.pk, 'A test'),
+                (self.c3.pk, 'Third'),
+            ])
+
     def test_num_queries(self):
         """
         Widgets that render multiple subwidgets shouldn't make more than one