diff --git a/tests/cts/hostside/app/src/com/android/cts/net/hostside/VpnTest.java b/tests/cts/hostside/app/src/com/android/cts/net/hostside/VpnTest.java
index cd3b650b05..454940f035 100755
--- a/tests/cts/hostside/app/src/com/android/cts/net/hostside/VpnTest.java
+++ b/tests/cts/hostside/app/src/com/android/cts/net/hostside/VpnTest.java
@@ -1726,10 +1726,21 @@ public class VpnTest {
         assertEquals(VpnManager.TYPE_VPN_SERVICE, ((VpnTransportInfo) ti).getType());
     }
 
-    private void assertDefaultProxy(ProxyInfo expected) {
+    private void assertDefaultProxy(ProxyInfo expected) throws Exception {
         assertEquals("Incorrect proxy config.", expected, mCM.getDefaultProxy());
         String expectedHost = expected == null ? null : expected.getHost();
         String expectedPort = expected == null ? null : String.valueOf(expected.getPort());
+
+        // ActivityThread may not have time to set it in the properties yet which will cause flakes.
+        // Wait for some time to deflake the test.
+        int attempt = 0;
+        while (!(Objects.equals(expectedHost, System.getProperty("http.proxyHost"))
+                && Objects.equals(expectedPort, System.getProperty("http.proxyPort")))
+                && attempt < 300) {
+            attempt++;
+            Log.d(TAG, "Wait for proxy being updated, attempt=" + attempt);
+            Thread.sleep(100);
+        }
         assertEquals("Incorrect proxy host system property.", expectedHost,
             System.getProperty("http.proxyHost"));
         assertEquals("Incorrect proxy port system property.", expectedPort,