diff --git a/tools/run_tests/run_interop_tests.py b/tools/run_tests/run_interop_tests.py
index 33ebcbcc41fd1f681606166033264a77cb5d2235..1814ba1abc3be2f45ce4ed69f8881948b1bd3dec 100755
--- a/tools/run_tests/run_interop_tests.py
+++ b/tools/run_tests/run_interop_tests.py
@@ -308,10 +308,10 @@ _LANGUAGES = {
 # languages supported as cloud_to_cloud servers
 _SERVERS = ['c++', 'node', 'csharp', 'java', 'go', 'ruby', 'python']
 
-# TODO(jtattermusch): add timeout_on_sleeping_server once java starts supporting it.
 _TEST_CASES = ['large_unary', 'empty_unary', 'ping_pong',
                'empty_stream', 'client_streaming', 'server_streaming',
-               'cancel_after_begin', 'cancel_after_first_response']
+               'cancel_after_begin', 'cancel_after_first_response',
+               'timeout_on_sleeping_server']
 
 _AUTH_TEST_CASES = ['compute_engine_creds', 'jwt_token_creds',
                     'oauth2_auth_token', 'per_rpc_creds']