How long it takes for a torn knee ligament to return to normal is related to the severity of the torn ligament, treatment, rehabilitation, and individual fitness. Patients with mild conditions usually recover in 4~6 weeks. Patients with complete ligament tears usually need 3~6 months to recover. 1. Patients with minor tears: conservative treatment is usually carried out and recovery can be achieved in 4~6 weeks. The recovery time will be increased for some patients who are physically weak and do not receive professional treatment in time. 2. Patients with serious degree of tearing: usually need to be treated by surgery, which takes a longer time for recovery, and also need to carry out the relevant rehabilitation treatment after surgery, and it usually takes 3~6 months for the patients to recover. It is recommended that patients consult a doctor in a timely manner, under the guidance of a professional doctor, to start rehabilitation treatment as soon as possible to help patients get the best recovery results, do not blindly treatment, to avoid the adverse consequences.