For example, if you want to change to, then:

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

Uncheck the Compact Empty Middle Packages option

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.