diff --git a/presubmit_canned_checks.py b/presubmit_canned_checks.py
index 209d65434..285077d9b 100644
--- a/presubmit_canned_checks.py
+++ b/presubmit_canned_checks.py
@@ -804,7 +804,7 @@ def CheckOwners(input_api, output_api, source_file_filter=None,
   if missing_files:
     output_list = [
         output('Missing %s for these files:\n    %s' %
-               (needed, '\n    '.join(missing_files)))]
+               (needed, '\n    '.join(sorted(missing_files))))]
     if not input_api.is_committing:
       suggested_owners = owners_db.reviewers_for(affected_files, owner_email)
       output_list.append(output('Suggested OWNERS:\n    %s' %
diff --git a/tests/presubmit_unittest.py b/tests/presubmit_unittest.py
index 243c9070f..9051e6d50 100755
--- a/tests/presubmit_unittest.py
+++ b/tests/presubmit_unittest.py
@@ -2419,9 +2419,11 @@ class CannedChecksUnittest(PresubmitTestsBase):
                                           'brett@example.com']),
                            reviewers=set(['john@example.com',
                                           'ben@example.com']),
-                           uncovered_files=set(['foo/xyz.cc']),
+                           uncovered_files=set(['foo/xyz.cc', 'foo/bar.cc']),
                            expected_output='Missing LGTM from an OWNER '
-                                           'for these files:\n    foo/xyz.cc\n',
+                                           'for these files:\n'
+                                           '    foo/bar.cc\n'
+                                           '    foo/xyz.cc\n',
                            author_counts_as_owner=False)
 
   def testCannedCheckOwners_TBR(self):