9 randomized controlled trials evaluating the effectiveness of t'ai chi in the treatment of osteoarthritis were included in this review, and 6 of these trials were included in the meta-analysis. Results indicated that when considering all types of control group protocols (i.e. attention control, waiting list, routine care and self-help programs), t'ai chi was significantly better than the control group in improving pain, physical function and joint stiffness and only minor adverse events were reported. However, subgroup analyses of the various types of control groups found that t'ai chi was significantly better in improving pain and physical function, but this significance was not present when evaluating joint stiffness. Lastly, a consensus was not reached when the effects of t'ai chi were evaluated in patients with OA in multiple joints.