After knee arthroscopy, different methods of rehabilitation exercise were adopted at different periods, quadriceps training, hip reduction training, straight leg raising training, quadriceps resistance exercise, ankle resistance exercise, lateral step exercise, anterior step exercise, one-legged semi-squatting exercise of the affected limb, weight-bearing training and so on. In the first postoperative week, quadriceps, hip reduction and straight leg raising exercises were performed, knee joint range of motion training was performed in the second week, normal range of motion training was performed in the third to fourth weeks, and muscle strength enhancement training was performed in the fifth week. 1. Postoperative week 1: Patients were trained in quadriceps and hip reduction 6 to 24 hours after surgery. During quadriceps training, the ankle joint is extended dorsally and the quadriceps is contracted after the knee joint is straightened. During the hip contraction exercise, the patient stays in the supine position and contracts the gluteal muscles. Straight leg raising exercise can ensure the stability of the patient’s knee. 2. Postoperative week 2: knee range of motion training should be carried out at this time. Training methods include quadriceps resistance exercise and ankle resistance exercise. 3. 3 to 4 weeks after surgery: normal range of motion training. Exercises include lateral stepping exercises and anterior stepping exercises. 4. Postoperative week 5: Strengthening muscle strength training. Training methods include single-leg half squatting exercises and weight-bearing exercises. Due to the different degree of damage to the knee, after arthroscopic surgery, a reasonable rehabilitation training program should be formulated under the guidance of a professional rehabilitation physician to carry out the training, and the patient should not arrange the training on his own, so as not to cause secondary damage to the knee.