diff --git a/README.md b/README.md
index 3f6f25a5..503ad615 100644
--- a/README.md
+++ b/README.md
@@ -453,6 +453,8 @@ marge-bot with `--embargo "Friday 1pm - Monday 9am" --branch-regexp master` and
 the other with `--branch-regexp (?!master)`. This would allow development to
 continue on other branches during the embargo on master.
 
+It is possible to restrict the source branches with `--source-branch-regexp`.
+
 ## Some handy git aliases
 
 Only `git bisect run` on commits that have passed CI (requires running marge-bot with `--add-tested`):
diff --git a/marge/app.py b/marge/app.py
index 6d057c72..07486431 100644
--- a/marge/app.py
+++ b/marge/app.py
@@ -197,6 +197,12 @@ def regexp(str_regex):
         default='.*',
         help='Only process MRs whose target branches match the given regular expression.\n',
     )
+    parser.add_argument(
+        '--source-branch-regexp',
+        type=regexp,
+        default='.*',
+        help='Only process MRs whose source branches match the given regular expression.\n',
+    )
     parser.add_argument(
         '--debug',
         action='store_true',
@@ -289,6 +295,7 @@ def main(args=None):
             git_timeout=options.git_timeout,
             git_reference_repo=options.git_reference_repo,
             branch_regexp=options.branch_regexp,
+            source_branch_regexp=options.source_branch_regexp,
             merge_order=options.merge_order,
             merge_opts=bot.MergeJobOptions.default(
                 add_tested=options.add_tested,
diff --git a/marge/bot.py b/marge/bot.py
index 1afb3f0e..398dde46 100644
--- a/marge/bot.py
+++ b/marge/bot.py
@@ -119,7 +119,20 @@ def _get_merge_requests(self, project, project_name):
                 'MRs that do not match branch_regexp: %s',
                 [mr.web_url for mr in filtered_out]
             )
-        return filtered_mrs
+        source_branch_regexp = self._config.source_branch_regexp
+        source_filtered_mrs = [mr for mr in filtered_mrs
+                               if source_branch_regexp.match(mr.source_branch)]
+        log.debug(
+            'MRs that match source_branch_regexp: %s',
+            [mr.web_url for mr in source_filtered_mrs]
+        )
+        source_filtered_out = set(filtered_mrs) - set(source_filtered_mrs)
+        if filtered_out:
+            log.debug(
+                'MRs that do not match source_branch_regexp: %s',
+                [mr.web_url for mr in source_filtered_out]
+            )
+        return source_filtered_mrs
 
     def _process_merge_requests(self, repo_manager, project, merge_requests):
         if not merge_requests:
@@ -174,7 +187,7 @@ def _get_single_job(self, project, merge_request, repo, options):
 
 class BotConfig(namedtuple('BotConfig',
                            'user ssh_key_file project_regexp merge_order merge_opts git_timeout ' +
-                           'git_reference_repo branch_regexp batch')):
+                           'git_reference_repo branch_regexp source_branch_regexp batch')):
     pass
 
 
diff --git a/tests/test_app.py b/tests/test_app.py
index 2de41a34..822a42c9 100644
--- a/tests/test_app.py
+++ b/tests/test_app.py
@@ -216,6 +216,12 @@ def test_branch_regexp():
             assert bot.config.branch_regexp == re.compile('foo.*bar')
 
 
+def test_source_branch_regexp():
+    with env(MARGE_AUTH_TOKEN="NON-ADMIN-TOKEN", MARGE_SSH_KEY="KEY", MARGE_GITLAB_URL='http://foo.com'):
+        with main("--source-branch-regexp='foo.*bar'") as bot:
+            assert bot.config.source_branch_regexp == re.compile('foo.*bar')
+
+
 def test_git_reference_repo():
     with env(MARGE_AUTH_TOKEN="NON-ADMIN-TOKEN", MARGE_SSH_KEY="KEY", MARGE_GITLAB_URL='http://foo.com'):
         with main("--git-reference-repo='/foo/reference_repo'") as bot: