Medial collateral ligament rehabilitation usually refers to the rehabilitation of medial collateral ligament injury of the knee, with different training according to early, middle and late rehabilitation, which mainly includes knee flexion and knee extension exercises. Early stage: Conservative treatment through braking, immobilization, rest, and bracing, as well as straight leg raising and other training to avoid muscle atrophy, relieve pain, and prevent edema. Middle and late stage: patients can do knee flexion and extension exercises after removing the fixed support, such as lying down and doing stirrups with both legs, straightening the legs in sitting position and then doing knee flexion, as well as squatting exercises, and knee joint stability training. In addition, resistance training and weight-bearing training can be added. It is recommended that the rehabilitation of medial collateral ligament patients should be carried out under the guidance of a rehabilitation doctor to avoid secondary injury and delayed condition.