diff --git a/gita/__main__.py b/gita/__main__.py
index 3428c41..fec01b3 100644
--- a/gita/__main__.py
+++ b/gita/__main__.py
@@ -23,7 +23,13 @@
 
 
 def f_add(args: argparse.Namespace):
-    utils.add_repos(args.paths)
+    repos = utils.get_repos()
+    utils.add_repos(repos, args.paths)
+
+
+def f_rename(args: argparse.Namespace):
+    repos = utils.get_repos()
+    utils.rename_repo(repos, args.repo[0], args.new_name)
 
 
 def f_ll(args: argparse.Namespace):
@@ -123,6 +129,17 @@ def main(argv=None):
         help="remove the chosen repo(s)")
     p_rm.set_defaults(func=f_rm)
 
+    p_rename = subparsers.add_parser('rename', help='rename a repo')
+    p_rename.add_argument(
+        'repo',
+        nargs=1,
+        choices=utils.get_repos(),
+        help="rename the chosen repo")
+    p_rename.add_argument(
+        'new_name',
+        help="new name")
+    p_rename.set_defaults(func=f_rename)
+
     ll_doc = f'''  status symbols:
     +: staged changes
     *: unstaged changes
@@ -153,8 +170,8 @@ def main(argv=None):
     # superman mode
     p_super = subparsers.add_parser(
         'super',
-        help=
-        'superman mode: delegate any git command/alias in specified or all repo(s).\n'
+        help='superman mode: delegate any git command/alias in specified or '
+        'all repo(s).\n'
         'Examples:\n \t gita super myrepo1 commit -am "fix a bug"\n'
         '\t gita super repo1 repo2 repo3 checkout new-feature')
     p_super.add_argument(
diff --git a/gita/utils.py b/gita/utils.py
index a4fb774..5978f51 100644
--- a/gita/utils.py
+++ b/gita/utils.py
@@ -34,17 +34,27 @@ def get_repos() -> Dict[str, str]:
     Return a `dict` of repo name to repo absolute path
     """
     path_file = get_path_fname()
-    paths = []
+    data = []
     if os.path.isfile(path_file) and os.stat(path_file).st_size > 0:
         with open(path_file) as f:
-            paths = f.read().splitlines()[0].split(os.pathsep)
-    data = ((os.path.basename(os.path.normpath(p)), p) for p in paths
-            if is_git(p))
+            # TODO: read lines one by one
+            #   for line in f:
+            data = f.read().splitlines()
+    # The file content is repos separated by :
+    # For each repo, there are path and repo name separated by ,
+    # If repo name is not provided, the basename of the path is used as name.
+    # For example, "/a/b/c,xx:/a/b/d:/c/e/f" corresponds to
+    # {xx: /a/b/c, d: /a/b/d, f: /c/e/f}
     repos = {}
-    for name, path in data:
+    for d in data:
+        if not d:  # blank line
+            continue
+        path, name = d.split(',')
+        if not is_git(path):
+            continue
         if name not in repos:
             repos[name] = path
-        else:
+        else:  # repo name collision for different paths: include parent path name
             par_name = os.path.basename(os.path.dirname(path))
             repos[os.path.join(par_name, name)] = path
     return repos
@@ -79,22 +89,39 @@ def is_git(path: str) -> bool:
     return os.path.exists(loc)
 
 
-def add_repos(new_paths: List[str]):
+def rename_repo(repos: Dict[str, str], repo: str, new_name: str):
+    """
+    Write new repo name to file
+    """
+    path = repos[repo]
+    del repos[repo]
+    repos[new_name] = path
+    _write_to_repo_file(repos, 'w')
+
+
+def _write_to_repo_file(repos: Dict[str, str], mode: str):
+    """
+    """
+    data = ''.join(f'{path},{name}\n' for name, path in repos.items())
+    fname = get_path_fname()
+    os.makedirs(os.path.dirname(fname), exist_ok=True)
+    with open(fname, mode) as f:
+        f.write(data)
+
+
+def add_repos(repos: Dict[str, str], new_paths: List[str]):
     """
     Write new repo paths to file
     """
-    existing_paths = set(get_repos().values())
+    existing_paths = set(repos.values())
     new_paths = set(os.path.abspath(p) for p in new_paths if is_git(p))
     new_paths = new_paths - existing_paths
     if new_paths:
-        print(f"Found {len(new_paths)} new repo(s):")
-        for path in new_paths:
-            print(path)
-        existing_paths.update(new_paths)
-        fname = get_path_fname()
-        os.makedirs(os.path.dirname(fname), exist_ok=True)
-        with open(fname, 'w') as f:
-            f.write(os.pathsep.join(sorted(existing_paths)))
+        print(f"Found {len(new_paths)} new repo(s).")
+        new_repos = {
+                os.path.basename(os.path.normpath(path)): path
+                for path in new_paths}
+        _write_to_repo_file(new_repos, 'a+')
     else:
         print('No new repos found!')
 
diff --git a/requirements.txt b/requirements.txt
index c76a568..3e9e127 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,4 @@
-pytest>=4.1.1
+pytest>=4.4.0
 pytest-cov>=2.6.1
 pytest-xdist>=1.26.0
 setuptools>=40.6.3
diff --git a/setup.py b/setup.py
index e496ba0..e1ba09d 100644
--- a/setup.py
+++ b/setup.py
@@ -7,7 +7,7 @@
 setup(
     name='gita',
     packages=['gita'],
-    version='0.9.7',
+    version='0.9.8',
     license='MIT',
     description='Manage multiple git repos',
     long_description=long_description,
diff --git a/tests/clash_path_file b/tests/clash_path_file
index 1ae1d50..4abbfca 100644
--- a/tests/clash_path_file
+++ b/tests/clash_path_file
@@ -1 +1,3 @@
-/a/bcd/repo1:/e/fgh/repo2:/root/x/repo1
+/a/bcd/repo1,repo1
+/e/fgh/repo2,repo2
+/root/x/repo1,repo1
diff --git a/tests/mock_path_file b/tests/mock_path_file
index 507368f..2a5f9f9 100644
--- a/tests/mock_path_file
+++ b/tests/mock_path_file
@@ -1 +1,4 @@
-/a/bcd/repo1:/e/fgh/repo2
+/a/bcd/repo1,repo1
+/a/b/c/repo3,xxx
+/e/fgh/repo2,repo2
+
diff --git a/tests/test_main.py b/tests/test_main.py
index a696f17..b64ac99 100644
--- a/tests/test_main.py
+++ b/tests/test_main.py
@@ -17,7 +17,7 @@ def testLl(self, mock_path_fname, capfd, tmp_path):
         __main__.main(['add', '.'])
         out, err = capfd.readouterr()
         assert err == ''
-        assert 'Found 1 new repo(s):' in out
+        assert 'Found 1 new repo(s).' in out
 
         # in production this is not needed
         utils.get_repos.cache_clear()
@@ -52,7 +52,7 @@ def testLs(self, monkeypatch, capfd):
 
     @pytest.mark.parametrize('path_fname, expected', [
         (PATH_FNAME,
-         "repo1 cmaster dsu\x1b[0m msg\nrepo2 cmaster dsu\x1b[0m msg\n"),
+         "repo1 cmaster dsu\x1b[0m msg\nrepo2 cmaster dsu\x1b[0m msg\nxxx   cmaster dsu\x1b[0m msg\n"),
         (PATH_FNAME_EMPTY, ""),
         (PATH_FNAME_CLASH,
          "repo1   cmaster dsu\x1b[0m msg\nrepo2   cmaster dsu\x1b[0m msg\nx/repo1 cmaster dsu\x1b[0m msg\n"
@@ -69,6 +69,7 @@ def testWithPathFiles(self, mock_path_fname, _0, _1, _2, _3, path_fname,
         utils.get_repos.cache_clear()
         __main__.main(['ll'])
         out, err = capfd.readouterr()
+        print(out)
         assert err == ''
         assert out == expected
 
diff --git a/tests/test_utils.py b/tests/test_utils.py
index 2e759aa..4c4c099 100644
--- a/tests/test_utils.py
+++ b/tests/test_utils.py
@@ -29,7 +29,8 @@ def test_describe(test_input, diff_return, expected, monkeypatch):
 @pytest.mark.parametrize('path_fname, expected', [
     (PATH_FNAME, {
         'repo1': '/a/bcd/repo1',
-        'repo2': '/e/fgh/repo2'
+        'repo2': '/e/fgh/repo2',
+        'xxx': '/a/b/c/repo3',
     }),
     (PATH_FNAME_EMPTY, {}),
     (PATH_FNAME_CLASH, {
@@ -70,22 +71,34 @@ def test_custom_push_cmd(_):
 @pytest.mark.parametrize(
     'path_input, expected',
     [
-        (['/home/some/repo/'], '/home/some/repo:/nos/repo'),  # add one new
+        (['/home/some/repo/'], '/home/some/repo,repo\n'),  # add one new
         (['/home/some/repo1', '/repo2'],
-         '/home/some/repo1:/nos/repo:/repo2'),  # add two new
+            {'/repo2,repo2\n/home/some/repo1,repo1\n',  # add two new
+            '/home/some/repo1,repo1\n/repo2,repo2\n'}),  # add two new
         (['/home/some/repo1', '/nos/repo'],
-         '/home/some/repo1:/nos/repo'),  # add one old one new
+         '/home/some/repo1,repo1\n'),  # add one old one new
     ])
 @patch('os.makedirs')
-@patch('gita.utils.get_repos', return_value={'repo': '/nos/repo'})
 @patch('gita.utils.is_git', return_value=True)
-def test_add_repos(_0, _1, _2, path_input, expected, monkeypatch):
+def test_add_repos(_0, _1, path_input, expected, monkeypatch):
     monkeypatch.setenv('XDG_CONFIG_HOME', '/config')
     with patch('builtins.open', mock_open()) as mock_file:
-        utils.add_repos(path_input)
-    mock_file.assert_called_with('/config/gita/repo_path', 'w')
+        utils.add_repos({'repo': '/nos/repo'}, path_input)
+    mock_file.assert_called_with('/config/gita/repo_path', 'a+')
     handle = mock_file()
-    handle.write.assert_called_once_with(expected)
+    if type(expected) == str:
+        handle.write.assert_called_once_with(expected)
+    else:
+        handle.write.assert_called_once()
+        args, kwargs = handle.write.call_args
+        assert args[0] in expected
+        assert not kwargs
+
+
+@patch('gita.utils._write_to_repo_file')
+def test_rename_repo(mock_write):
+    utils.rename_repo({'r1': '/a/b', 'r2': '/c/c'}, 'r2', 'xxx')
+    mock_write.assert_called_once_with({'r1': '/a/b', 'xxx': '/c/c'}, 'w')
 
 
 def test_async_output(capfd):