diff --git a/tempest/cmd/run.py b/tempest/cmd/run.py
index 2669ff7..e305646 100644
--- a/tempest/cmd/run.py
+++ b/tempest/cmd/run.py
@@ -269,6 +269,8 @@
                 return_code = commands.run_command(
                     **params, blacklist_file=ex_list,
                     whitelist_file=in_list, black_regex=ex_regex)
+            if parsed_args.slowest:
+                commands.slowest_command()
             if return_code > 0:
                 sys.exit(return_code)
         return return_code
@@ -392,6 +394,9 @@
                             help='Combine the output of this run with the '
                                  "previous run's as a combined stream in the "
                                  "stestr repository after it finish")
+        parser.add_argument('--slowest', action='store_true',
+                            help='Show the longest running tests in the '
+                                 'stestr repository after it finishes')
 
         parser.set_defaults(parallel=True)
         return parser
diff --git a/tempest/tests/cmd/test_run.py b/tempest/tests/cmd/test_run.py
index 3b5e901..b487c3f 100644
--- a/tempest/tests/cmd/test_run.py
+++ b/tempest/tests/cmd/test_run.py
@@ -225,6 +225,11 @@
                             '%s=%s' % (self.exclude_list, path),
                             '--regex', 'fail'], 1)
 
+    def test_tempest_run_with_slowest(self):
+        out, err = self.assertRunExit(['tempest', 'run', '--regex', 'passing',
+                                       '--slowest'], 0)
+        self.assertRegex(str(out), r'Test id\s+Runtime \(s\)')
+
 
 class TestOldArgRunReturnCode(TestRunReturnCode):
     """A class for testing deprecated but still supported args.
@@ -363,6 +368,7 @@
         parsed_args.state = None
         parsed_args.list_tests = False
         parsed_args.config_file = path
+        parsed_args.slowest = False
 
         with mock.patch('stestr.commands.run_command') as m:
             m.return_value = 0
@@ -393,6 +399,7 @@
         parsed_args.state = None
         parsed_args.list_tests = False
         parsed_args.config_file = path
+        parsed_args.slowest = False
 
         with mock.patch('stestr.commands.run_command') as m:
             m.return_value = 0
@@ -409,6 +416,7 @@
         parsed_args.state = None
         parsed_args.list_tests = False
         parsed_args.config_file = ''
+        parsed_args.slowest = False
 
         with mock.patch('stestr.commands.run_command') as m:
             m.return_value = 0
@@ -441,6 +449,7 @@
         parsed_args.state = True
         parsed_args.list_tests = False
         parsed_args.config_file = ''
+        parsed_args.slowest = False
 
         with mock.patch('stestr.commands.run_command') as m:
             m.return_value = 0
@@ -460,6 +469,7 @@
         parsed_args.state = True
         parsed_args.list_tests = False
         parsed_args.config_file = path
+        parsed_args.slowest = False
 
         with mock.patch('stestr.commands.run_command') as m:
             m.return_value = 0