diff --git a/scripts/test_config_fixer.py b/scripts/test_config_fixer.py
index 3dbc22e..07e01a1 100644
--- a/scripts/test_config_fixer.py
+++ b/scripts/test_config_fixer.py
@@ -31,6 +31,8 @@
 KNOWN_PREPARERS = ['com.android.tradefed.targetprep.TestAppInstallSetup',
                    'com.android.tradefed.targetprep.suite.SuiteApkInstaller']
 
+MAINLINE_CONTROLLER = 'com.android.tradefed.testtype.suite.module.MainlineTestModuleController'
+
 def parse_args():
   """Parse commandline arguments."""
 
@@ -41,6 +43,8 @@
                       help=('overwrite package fields in the test config'))
   parser.add_argument('--test-file-name', default='', dest='test_file_name',
                       help=('overwrite test file name in the test config'))
+  parser.add_argument('--mainline-package-name', default='', dest='mainline_package_name',
+                      help=('overwrite mainline module package name in the test config'))
   parser.add_argument('input', help='input test config file')
   parser.add_argument('output', help='output test config file')
   return parser.parse_args()
@@ -72,6 +76,16 @@
         if option.getAttribute('name') == "test-file-name":
           option.setAttribute('value', test_file_name)
 
+def overwrite_mainline_module_package_name(test_config_doc, mainline_package_name):
+
+  test_config = parse_test_config(test_config_doc)
+
+  for obj in get_children_with_tag(test_config, 'object'):
+    if obj.getAttribute('class') == MAINLINE_CONTROLLER:
+      for option in get_children_with_tag(obj, 'option'):
+        if option.getAttribute('name') == "mainline-module-package-name":
+          option.setAttribute('value', mainline_package_name)
+
 def main():
   """Program entry point."""
   try:
@@ -88,6 +102,9 @@
     if args.test_file_name:
       overwrite_test_file_name(doc, args.test_file_name)
 
+    if args.mainline_package_name:
+      overwrite_mainline_module_package_name(doc, args.mainline_package_name)
+
     with open(args.output, 'w') as f:
       write_xml(f, doc)
 
diff --git a/scripts/test_config_fixer_test.py b/scripts/test_config_fixer_test.py
index 39ce5b3..699f91e 100644
--- a/scripts/test_config_fixer_test.py
+++ b/scripts/test_config_fixer_test.py
@@ -23,6 +23,8 @@
 
 import test_config_fixer
 
+from manifest import write_xml
+
 sys.dont_write_bytecode = True
 
 
@@ -117,5 +119,39 @@
     self.assertEqual(expected, output.getvalue())
 
 
+class OverwriteMainlineModulePackageNameTest(unittest.TestCase):
+  """ Unit tests for overwrite_mainline_module_package_name function """
+
+  test_config = (
+      '<?xml version="1.0" encoding="utf-8"?>\n'
+      '<configuration description="Runs some tests.">\n'
+      '    <target_preparer class="com.android.tradefed.targetprep.TestAppInstallSetup">\n'
+      '        <option name="test-file-name" value="foo.apk"/>\n'
+      '    </target_preparer>\n'
+      '    <test class="com.android.tradefed.testtype.AndroidJUnitTest">\n'
+      '        <option name="package" value="com.android.foo"/>\n'
+      '        <option name="runtime-hint" value="20s"/>\n'
+      '    </test>\n'
+      '    <object type="module_controller" class="com.android.tradefed.testtype.suite.module.MainlineTestModuleController">\n'
+      '        <option name="enable" value="true"/>\n'
+      '        <option name="mainline-module-package-name" value="%s"/>\n'
+      '    </object>\n'
+      '</configuration>\n')
+
+  def test_testappinstallsetup(self):
+    doc = minidom.parseString(self.test_config % ("com.android.old.package.name"))
+
+    test_config_fixer.overwrite_mainline_module_package_name(doc, "com.android.new.package.name")
+    output = io.StringIO()
+    test_config_fixer.write_xml(output, doc)
+
+    # Only the mainline module package name should be updated. Format the xml
+    # with minidom first to avoid mismatches due to trivial reformatting.
+    expected = io.StringIO()
+    write_xml(expected, minidom.parseString(self.test_config % ("com.android.new.package.name")))
+    self.maxDiff = None
+    self.assertEqual(expected.getvalue(), output.getvalue())
+
+
 if __name__ == '__main__':
   unittest.main(verbosity=2)