diff --git a/src/com/android/phone/PhoneInterfaceManager.java b/src/com/android/phone/PhoneInterfaceManager.java
index 706373b..809b1c2 100644
--- a/src/com/android/phone/PhoneInterfaceManager.java
+++ b/src/com/android/phone/PhoneInterfaceManager.java
@@ -2608,6 +2608,9 @@
          * If PUK is null, unlock SIM card with PIN
          *
          * If PUK is not null, unlock SIM card with PUK and set PIN code
+         *
+         * Besides, since it is reused in class level, the thread's looper will be stopped to avoid
+         * its thread leak.
          */
         synchronized int[] unlockSim(String puk, String pin) {
 
@@ -2643,6 +2646,8 @@
             if (mResult == PhoneConstants.PIN_RESULT_SUCCESS && pin.length() > 0) {
                 UiccController.getInstance().getPinStorage().storePin(pin, mPhoneId);
             }
+            // This instance is no longer reused, so quit its thread's looper.
+            mHandler.getLooper().quitSafely();
 
             return resultArray;
         }