Does app will be removed in installed phones if the app unpublished from AppStore? I have an app which is in live (Published in AppStore). Now if I would removed that app from AppStore ,can that app still able to use in already installed phones? 

Or is there anyway to do the same by other way? I wanted that my app cant used by anyone even they have installed it.
No, removing your app from the App Store won't remove it from other people's devices (iPhones/iPads).

Yes, an app that was removed from the App Store but is still installed on a user's device. If the app relies on data from another server (getting data from a database or a news source) an this data cannot be accessed anymore at least parts of the app won'be functional anymore.