diff --git a/django/db/migrations/operations/models.py b/django/db/migrations/operations/models.py
index 2855107e0e..eabffa1b7d 100644
--- a/django/db/migrations/operations/models.py
+++ b/django/db/migrations/operations/models.py
@@ -590,6 +590,7 @@ class AlterModelManagers(Operation):
     def state_forwards(self, app_label, state):
         model_state = state.models[app_label, self.name_lower]
         model_state.managers = list(self.managers)
+        state.reload_model(app_label, self.name_lower)
 
     def database_forwards(self, app_label, schema_editor, from_state, to_state):
         pass
diff --git a/docs/releases/1.8.8.txt b/docs/releases/1.8.8.txt
index 5dca5bccdb..6ba76d71cb 100644
--- a/docs/releases/1.8.8.txt
+++ b/docs/releases/1.8.8.txt
@@ -34,3 +34,6 @@ Bugfixes
 * Fixed missing ``varchar/text_pattern_ops`` index on ``CharField`` and
   ``TextField`` respectively when using ``AlterField`` on PostgreSQL
   (:ticket:`25412`).
+
+* Fixed a state bug when using an ``AlterModelManagers`` operation
+  (:ticket:`25852`).
diff --git a/docs/releases/1.9.1.txt b/docs/releases/1.9.1.txt
index 520c2b3c31..25acbd540b 100644
--- a/docs/releases/1.9.1.txt
+++ b/docs/releases/1.9.1.txt
@@ -40,3 +40,6 @@ Bugfixes
 
 * Fixed evaluation of zero-length slices of ``QuerySet.values()``
   (:ticket:`25894`).
+
+* Fixed a state bug when using an ``AlterModelManagers`` operation
+  (:ticket:`25852`).
diff --git a/tests/migrations/test_operations.py b/tests/migrations/test_operations.py
index 51d4d5bbbb..b624a73392 100644
--- a/tests/migrations/test_operations.py
+++ b/tests/migrations/test_operations.py
@@ -1393,6 +1393,11 @@ class OperationTests(OperationTestBase):
         self.assertEqual(managers[2][0], "food_mgr_kwargs")
         self.assertIsInstance(managers[2][1], FoodManager)
         self.assertEqual(managers[2][1].args, ("x", "y", 3, 4))
+        rendered_state = new_state.apps
+        model = rendered_state.get_model('test_almoma', 'pony')
+        self.assertIsInstance(model.food_qs, models.Manager)
+        self.assertIsInstance(model.food_mgr, FoodManager)
+        self.assertIsInstance(model.food_mgr_kwargs, FoodManager)
 
     def test_alter_model_managers_emptying(self):
         """