How long it takes to walk after a medial collateral ligament injury is related to the degree of the injury. Generally speaking, you can walk with weight on the ground after 2 weeks in the case of a mild injury, and after 4 to 6 weeks in the case of a severe injury. The medial collateral ligament of the knee is categorized into three degrees according to the degree of injury. Injury of degree Ⅰ and Ⅱ refers to mild or insecure injury of medial collateral ligament ligament, the knee joint should be rested and braked, and the method of fixation with a brace should be adopted, and the knee joint can be put down on the ground and walk with weight-bearing after 2 weeks of treatment in general. Third degree injury refers to the complete rupture of the medial collateral ligament, which needs to be immobilized with a brace for 4~6 weeks before weight-bearing walking on the ground. If accompanied by joint capsule damage, it is necessary to take surgical treatment, to carry out incision and exploration and repair of medial collateral ligament, and it is possible to consider walking on the ground with weight-bearing gradually only after 4~6 weeks of the operation. Patients with medial collateral ligament injury of the knee should actively cooperate with the doctor, carry out standardized treatment, regular review, and promote early recovery.