Objective To analyze the effect of rapid rehabilitation exercise on postoperative joint mobility of patients with knee joint varus deformity after total knee arthroplasty. Methods 76 patients with knee varus deformity caused by knee osteoarthritis were enrolled in our hospital from May 2016 to May 2017. All patients underwent total knee arthroplasty. After surgery, 38 cases were recovered by active and rapid rehabilitation (study group) and 38 cases were performed using conventional rehabilitation method (control group) The knee activity, knee function (HSS) score, knee varus angle, knee maximum flexion angle, knee maximum angle of extension and quality of life score of patients were compared before and after surgery. Results Compared with the before operation, the knee activity, knee function (HSS) score, knee maximum flexion angle were significantly increased in the two groups after operation, and knee varus angle and the maximal angle of knee joint significantly decreased (P＜0.01). Compared with the control group, except knee varus angle, the changes of the other indexes were more obvious in study group (P＜0.01 or P＜0.05). In addition, after intervention of exercise, the scores of the quality of life items in the two groups were significantly increased (P＜0.01), and the scores of physical function, somatic character, body pain, total health, social function and emotional role in patients with rapid rehabilitation exercise were significantly higher than control group (P＜0.05 or P＜0.01). Conclusion After total knee arthroplasty of patients with knee joint varus deformity, active and rapid rehabilitation is beneficial to the recovery of knee joint activity, which is better than conventional rehabilitation exercise.