B.J. Penn net worth: B.J. Penn is an American mixed martial artist and Brazilian Jiu-Jitsu practitioner who has a net worth of $22 million. B.J. Penn has earned his net worth as a competitor in the Ultimate Fighting Championship. In the World Jiu-Jitsu Championship in the black-belt category Penn is the first non-Brazilian winner. He is a former UFC Lightweight Champion and UFC Welterweight Champion. He is only the second fighter in UFC history to win titles in two different weight classes. Penn also served as a coach on The Ultimate Fighter 5 reality show. Nicknamed "The Prodigy" B.J. was born in Kailua, Hawaii.