diff --git a/zerver/lib/streams.py b/zerver/lib/streams.py
index 46870181ba..a62aee51bc 100644
--- a/zerver/lib/streams.py
+++ b/zerver/lib/streams.py
@@ -102,14 +102,16 @@ def check_stream_name_available(realm: Realm, name: str) -> None:
         pass
 
 def access_stream_by_name(user_profile: UserProfile,
-                          stream_name: str) -> Tuple[Stream, Recipient, Optional[Subscription]]:
+                          stream_name: str,
+                          allow_realm_admin: bool=False) -> Tuple[Stream, Recipient, Optional[Subscription]]:
     error = _("Invalid stream name '%s'" % (stream_name,))
     try:
         stream = get_realm_stream(stream_name, user_profile.realm_id)
     except Stream.DoesNotExist:
         raise JsonableError(error)
 
-    (recipient, sub) = access_stream_common(user_profile, stream, error)
+    (recipient, sub) = access_stream_common(user_profile, stream, error,
+                                            allow_realm_admin=allow_realm_admin)
     return (stream, recipient, sub)
 
 def access_stream_for_unmute_topic(user_profile: UserProfile, stream_name: str, error: str) -> Stream:
diff --git a/zerver/tests/test_subs.py b/zerver/tests/test_subs.py
index 1938c736e0..5f6e42741e 100644
--- a/zerver/tests/test_subs.py
+++ b/zerver/tests/test_subs.py
@@ -1039,6 +1039,24 @@ class DefaultStreamTest(ZulipTestCase):
         self.assert_json_success(result)
         self.assertFalse(stream_name in self.get_default_stream_names(user_profile.realm))
 
+        # Test admin can't add unsubscribed private stream
+        stream_name = "private_stream"
+        self.make_stream(stream_name, invite_only=True)
+        self.subscribe(self.example_user('iago'), stream_name)
+        result = self.client_post('/json/default_streams', dict(stream_name=stream_name))
+        self.assert_json_error(result, "Invalid stream name '%s'" % (stream_name))
+
+        self.subscribe(user_profile, stream_name)
+        result = self.client_post('/json/default_streams', dict(stream_name=stream_name))
+        self.assert_json_success(result)
+        self.assertTrue(stream_name in self.get_default_stream_names(user_profile.realm))
+
+        # Test admin can remove unsubscribed private stream
+        self.unsubscribe(user_profile, stream_name)
+        result = self.client_delete('/json/default_streams', dict(stream_name=stream_name))
+        self.assert_json_success(result)
+        self.assertFalse(stream_name in self.get_default_stream_names(user_profile.realm))
+
 class DefaultStreamGroupTest(ZulipTestCase):
     def test_create_update_and_remove_default_stream_group(self) -> None:
         realm = get_realm("zulip")
diff --git a/zerver/views/streams.py b/zerver/views/streams.py
index 8b512b76b0..9987e87d3f 100644
--- a/zerver/views/streams.py
+++ b/zerver/views/streams.py
@@ -136,7 +136,8 @@ def remove_default_stream_group(request: HttpRequest, user_profile: UserProfile,
 def remove_default_stream(request: HttpRequest,
                           user_profile: UserProfile,
                           stream_name: str=REQ()) -> HttpResponse:
-    (stream, recipient, sub) = access_stream_by_name(user_profile, stream_name)
+    (stream, recipient, sub) = access_stream_by_name(user_profile, stream_name,
+                                                     allow_realm_admin=True)
     do_remove_default_stream(stream)
     return json_success()