Abstract: Objective To observe the clinical effects of the Joint Active System on the treatment of joint dysfunction after deep burn. Methods Twenty-two patients with joint dysfunction after deep burn were hospitalized in Institute of Burns of Tongren Hospital of Wuhan University & Wuhan Third Hospital from January 2015 to October 2016, involving 18 elbow joints with flexion disorder, 10 wrist joints with dorsal extension disorder, and 12 ankle joints with dorsal extension disorder. They were treated with the elbow joint activity training device, the wrist joint activity training device, and the ankle joint activity training device of the Joint Active System, respectively. The treatment was carried out 3 times each day with interval of 6 h, 30 minutes each time, and it lasted for four to seven months, with one month as a course of treatment. Before treatment and 1, 2, 3, 4 month (s) after, active motion range of each joint was measured by joint goniometer. Function improvement of each joint was evaluated, and the total effective ratio was calculated 4 months after treatment. Satisfaction degree of patients was assessed by the modified Likert Scale 1, 2, 3, 4 month (s) after treatment. Data were processed with one-way analysis of variance for repeated measurement and LSD test. Results Before treatment and 1, 2, 3, 4 month (s) after, flexion active motion range of elbow joints were (61±23), (78±22), (89±20), (96±20), and (103±19)°; dorsal extension active motion range of wrist joints were (23±7), (31±6), (38±9), (44±5), and (49±8)°; dorsal extension active motion range of ankle joints were (-31±12), (-23±10), (-16±7), (-12±6), and (-8±4)°, respectively. The active motion range of each joint was obviously higher 1, 2, 3, 4 month (s) after treatment than the previous time point of the same joint (with P values below 0.01). Four months after treatment, the total effective ratios of function improvement of elbow joints, wrist joints, and ankle joints were 5/6, 9/10, and 2/3, respectively. Scores of satisfaction degree of the patients 1, 2, 3, 4 month (s) after treatment were (1.3±0.7), (2.2±1.0), (2.8±0.8), and (3.3±0.6) points, respectively. Scores of satisfaction degree of the patients were obviously higher 2, 3, 4 months after treatment than the previous time point (with P values below 0.05). Conclusions Joint Active System can improve the active range of motion of each joint obviously in treating joint dysfunction after deep burn, with total effective ratio of function improvement of each joint surpassing 0.66, and the majority of patients are quite satisfied with the curative effects.