diff --git a/django/db/models/sql/query.py b/django/db/models/sql/query.py
index da34694fed..775dfae772 100644
--- a/django/db/models/sql/query.py
+++ b/django/db/models/sql/query.py
@@ -329,7 +329,7 @@ class BaseQuery(object):
         Performs a COUNT() query using the current filter constraints.
         """
         obj = self.clone()
-        if len(self.select) > 1:
+        if len(self.select) > 1 or self.aggregate_select:
             # If a select clause exists, then the query has already started to
             # specify the columns that are to be returned.
             # In this case, we need to use a subquery to evaluate the count.
@@ -1950,6 +1950,7 @@ class BaseQuery(object):
         # Clear out the select cache to reflect the new unmasked aggregates.
         self.aggregates = {None: count}
         self.set_aggregate_mask(None)
+        self.group_by = None
 
     def add_select_related(self, fields):
         """
diff --git a/tests/regressiontests/aggregation_regress/models.py b/tests/regressiontests/aggregation_regress/models.py
index f2763d5c04..275ea07390 100644
--- a/tests/regressiontests/aggregation_regress/models.py
+++ b/tests/regressiontests/aggregation_regress/models.py
@@ -252,6 +252,13 @@ FieldError: Cannot resolve keyword 'foo' into field. Choices are: authors, conta
 >>> [int(x['sheets']) for x in qs]
 [150, 175, 224, 264, 473, 566]
 
+# Regression for 10425 - annotations don't get in the way of a count() clause
+>>> Book.objects.values('publisher').annotate(Count('publisher')).count()
+4
+
+>>> Book.objects.annotate(Count('publisher')).values('publisher').count()
+6
+
 """
 }