Increased production of reactive oxygen species (ROS) contributing to oxidative stress, significantly influences many diseases including temporomandibular joint (TMJ) disorder. Temporomandibular joint disorder (TMJD) is an inflammatory disease which emphasizes that mechanical stresses lead to the oxidative stress of articular tissues. But, studies on the defense mechanism against oxidative stress in the pathogenesis of TMJD have received little attention. Hence, we made a novel attempt to review the pathogenesis of TMJD to explore the possible role of ROS in the degenerative TMJ disease.