By default, the Facebook app for Android
will run in the language option set on your device. However, if you'd like to use a different language on the application, you can adjust your language settings in just a few simple steps. Here's how to do so.
Change Language Settings on the Facebook App
Open the Facebook app and tap the Menu
option. Then, scroll to Help and Settings
Next, select App Settings
> General Settings
Tap the Language
option, and then make your selection:
Your new settings will be applied right away.