diff --git a/django/contrib/gis/db/backends/postgis/adapter.py b/django/contrib/gis/db/backends/postgis/adapter.py
index 0e02427811..20b0327d5c 100644
--- a/django/contrib/gis/db/backends/postgis/adapter.py
+++ b/django/contrib/gis/db/backends/postgis/adapter.py
@@ -42,7 +42,7 @@ class PostGISAdapter:
         return hash(self.ewkb)
 
     def __str__(self):
-        return self.getquoted()
+        return self.getquoted().decode()
 
     @classmethod
     def _fix_polygon(cls, poly):
diff --git a/tests/gis_tests/geoapp/tests.py b/tests/gis_tests/geoapp/tests.py
index 0a71639c84..fd5fc3c793 100644
--- a/tests/gis_tests/geoapp/tests.py
+++ b/tests/gis_tests/geoapp/tests.py
@@ -212,6 +212,14 @@ class GeoModelTest(TestCase):
         with self.assertNumQueries(0):  # Ensure point isn't deferred.
             self.assertIsInstance(cities2[0].point, Point)
 
+    def test_gis_query_as_string(self):
+        """GIS queries can be represented as strings."""
+        query = City.objects.filter(point__within=Polygon.from_bbox((0, 0, 2, 2)))
+        self.assertIn(
+            connection.ops.quote_name(City._meta.db_table),
+            str(query.query),
+        )
+
     def test_dumpdata_loaddata_cycle(self):
         """
         Test a dumpdata/loaddata cycle with geographic data.