Knee pain after running half-marathon is mainly considered to be related to acute joint injuries, osteoarthritis and meniscus injuries, etc., and should be treated in a timely manner with general treatment, drug therapy and other therapeutic interventions, and only standardized treatment can be quickly improved. 1. Acute joint injury: too much activity or too strenuous when running can lead to acute injury of joint tissues and cause pain symptoms. Patients should rest in bed and take ice packs to deal with it, and after 72 hours, it can be dealt with by hot packs. 2. Osteoarthritis: After strenuous exercise, osteoarthritis can lead to an acute attack, resulting in knee pain. For this symptom, in addition to strengthening rest, can also follow the doctor’s instructions to apply chondroitin sulfate, sodium hyaluronate and other drugs for treatment. After the use of drugs appear nausea, skin rash and other adverse reactions, must promptly seek medical attention. 3. Meniscus injury: Meniscus injury after running can also cause knee pain. This symptom should be treated with meniscus repair or meniscectomy according to the condition. The symptoms of knee pain after running a half-marathon may also be related to osteophytes, patellofemoral joint degeneration, knee bursitis and other diseases, and it is recommended that the patient consult a doctor in a timely manner and follow the medical advice for treatment.