--- a/dom/nfc/gonk/Nfc.js
+++ b/dom/nfc/gonk/Nfc.js
@@ -173,18 +173,20 @@ XPCOMUtils.defineLazyGetter(this, "gMess
         dump("invalid target");
         return;
       }
 
       target.sendAsyncMessage("NFC:DOMEvent", options);
     },
 
     setFocusApp: function setFocusApp(id, isFocus) {
-      // if calling setNFCFocus(true) on the same browser-element, ignore.
-      if (isFocus && (id == this.focusApp)) {
+      // if calling setNFCFocus(true) on the browser-element which is already
+      // focused, or calling setNFCFocus(false) on the browser-element which has
+      // lost focus already, ignore.
+      if (isFocus == (id == this.focusApp)) {
         return;
       }
 
       if (this.focusApp != NFC.SYSTEM_APP_ID) {
         this.onFocusChanged(this.focusApp, false);
       }
 
       if (isFocus) {