diff --git a/testing/config/mozharness/b2g_emulator_config.py b/testing/config/mozharness/b2g_emulator_config.py
index 602194d71569..a6244ceff107 100644
--- a/testing/config/mozharness/b2g_emulator_config.py
+++ b/testing/config/mozharness/b2g_emulator_config.py
@@ -19,7 +19,7 @@ config = {
         "--remote-webserver=%(remote_webserver)s", "%(test_manifest)s",
         "--xre-path=%(xre_path)s", "--symbols-path=%(symbols_path)s", "--busybox=%(busybox)s",
         "--total-chunks=%(total_chunks)s", "--this-chunk=%(this_chunk)s",
-        "--quiet",
+        "--quiet", "--certificate-path=%(certificate_path)s",
     ],
 
     "reftest_options": [