Joe Rogan has never fought in the UFC or anywhere under MMA rules. He was a Taekwondo champion in his youth, however, and is currently a black belt in Jiu-Jitsu under Jean Jacques Machado. He is also a black belt under Eddie Bravo's No-Gi system of Jiu-Jitsu, 10th Planet.
Joe Rogan provides his reservation for not competing in MMA despite training. The UFC commentator revealed to his guest, Howie Mandel, on JRE #1971 that he still trains in martial arts. However, Rogan added that he does not compete in the sport owing to his age.