diff --git a/src/ianitor/args_parser.py b/src/ianitor/args_parser.py
index 1249400..e0107f4 100644
--- a/src/ianitor/args_parser.py
+++ b/src/ianitor/args_parser.py
@@ -143,6 +143,7 @@ def get_parser():
 
     parser.add_argument(
         "--port",
+        type=int,
         help="set service port",
     )
 
diff --git a/tests/test_args_parser.py b/tests/test_args_parser.py
index 99ef445..3896ab9 100644
--- a/tests/test_args_parser.py
+++ b/tests/test_args_parser.py
@@ -45,6 +45,12 @@ def test_parse_args():
     args, invocation = args_parser.parse_args()
     assert invocation == ['tail', '-f', 'something']
 
+
+@patch('sys.argv', ["ianitor", "tailf", '--port', '1234', '--', 'tail', '-f', 'something'])  # noqa
+def test_parse_port():
+    args, invocation = args_parser.parse_args()
+    assert args.port == 1234
+
 TEST_TTL = 100