Knee pain after squatting can be caused by the following reasons: first, patellofemoral arthritis of the knee joint, when there is chronic inflammation between the patella and the femur of the knee joint resulting in cartilage damage, there can be symptoms of knee pain after squatting, which should be diagnosed by early examination of knee x-ray and MRI. Second, meniscal damage, when the posterior horn of the meniscus of the knee joint has tears, injury, can have squatting up after the knee pain symptoms, this time to check the early meniscal MRI to diagnose. Third, knee osteoarthritis, when the knee osteoarthritis is serious, it can involve the cartilage, meniscus, surrounding soft tissues and lead to injury, which can lead to knee pain after squatting, then we should take knee X-ray, CT to early diagnosis and treatment.