Yes, JIUJITSU is a Scrabble word!

Letter values in Scrabble US: J 8, I 1, U 1, J 8, I 1, T 1, S 1, U 1.

Is it a valid word?

JIUJITSU is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

a method of self-defense without weapons that was developed in China and Japan; holds and blows are supplemented by clever use of the attacker's own weight and strength