Do the Pokemon lose levels they gained if they faint in the same battle

pokemon-fifth-generation

If I am in a battle against a trainer with multiple Pokemon, and I beat one of them, and my Pokemon gains a level or two, but against the next Pokemon, it faints, will I lose the levels that my Pokemon gained?

Best Answer

Nope. Once a pokemon has been assigned experience, fainting won't take it away from them.

In the extreme case, you can have a pokemon level up to an evolution trigger, then faint, then finish the battle, and they will evolve, despite being KO'd.