For example, if you want to change com.example.app to my.awesome.game, then:

In your Project pane, click on the little gear icon (Gears icon)

Uncheck the Compact Empty Middle Packages optionhttps://i.stack.imgur.com/lkezT.png

Your package directory will now be broken up into individual directories

Individually select each directory you want to rename, and:

Right-click it Select Refactor Click on Rename In the pop-up dialog, click on Rename Package instead of Rename Directory Enter the new name and hit Refactor Click Do Refactor in the bottom Allow a minute to let Android Studio update all changes

Note: When renaming com in Android Studio, it might give a warning. In such case, select Rename All

Now open your Gradle Build File (build.gradle - Usually app or mobile). Update the applicationId in the defaultConfig to your new Package Name and Sync Gradle, if it hasn’t already been updated automatically:

You may need to change the package= attribute in your manifest.
Clean and Rebuild.

Done! Anyway, Android Studio needs to make this process a little simpler.