After posterior cruciate ligament reconstruction surgery, rehabilitation training is needed to restore the function of the limb, and the corresponding exercises are performed according to the recovery time, as follows: 1. One week after surgery: within one week after surgery is the edema period, at which time the patient needs to rest in bed and fix the patient’s knee joint. Patients can do active ankle flexion and extension training in bed, doing 4-6 sets of 20 times each day. In addition, you can also do quadriceps isometric contraction training, straight leg raising training, the above actions are done three sets per day, each group do about 30 times. 2, 2-3 weeks after surgery: you can do flexion and extension knee training under the protection of the brace, to actively flex and extend the knee joint, do four sets per day, each group do about 30. 3, 4-8 weeks after surgery: the active knee flexion and extension need to reach about 90 degrees, and continue to strengthen 4. 8-12 weeks after surgery: according to the recovery situation, the knee joint can be gradually taken off the crutches and normal walking function can be restored.