With the arrival of spring and the increase in outdoor sports among adolescents, it is common to see young adults with hip pain in outpatient clinics. In our country, the most common causes of hip pain are ischemic necrosis of the femoral head, hip dysplasia, and inflammatory diseases of the hip such as ankylosing spondylitis. However, some of these patients have insidious symptoms of hip pain, with a slow course and little hip deformity, making it difficult to diagnose the disease. Hip pain in adolescents is a warning against hip impingement syndrome. Hip impingement syndrome, also known as femoroacetabular impingement syndrom e (FA I), has been a hot topic in international joint surgery clinical research in recent years. This syndrome is considered to be one of the pathogenic mechanisms leading to osteoarthritis of the hip, and it has clear clinical features, imaging manifestations, and diagnostic methods. Patients have a history of hip pain or hip sprain. Most of them have unilateral onset, and occasionally bilateral pain. Most of the patients complained of pain in the groin or deep buttocks, and some had pain in the anterior thigh and knee as the first symptom. The nature of the pain is mostly vague, with obvious soreness and swelling. Often pain when starting, pain and discomfort after walking long distances, but walking distance on the road is not significantly limited. Some patients have pain when squatting or cross-legged. Some patients have obvious joint flickering pain and joint interlocking symptoms, and some patients have different degrees of joint popping. Orthopedic examination: Most of the patients have normal hip mobility, some patients have different degrees of hip rotation limitation, among which internal rotation limitation is obvious, and the patients can trigger hip pain when the hip joint is extremely flexed in internal or external rotation position, and the 4-word test of the hip joint is positive (pain or limitation of hip abduction and external rotation activities), and some patients can touch the popping sound of the hip joint during the activities of flexion and extension of the hip joint. Imaging: anteroposterior and lateral radiographs of both hips. Anteroposterior and lateral radiographs showed different degrees of pistol grip deformity of the femoral head; lateral radiographs showed bony elevation at the femoral head-neck junction or acetabular retroversion deformity; CT radiographs showed acetabular retroversion in coronal position; axial radiographs of the femoral neck showed bony elevation at the femoral head-neck junction, with a significantly increased angle, and an abnormal eccentricity of the femoral neck; and MRI imaging showed glenoid labral tear in most of the patients with varying degrees of severity. Treatment: Most of the patients chose conservative treatment because hip pain did not affect their daily life and work significantly. Conservative treatment includes avoidance of heavy labor, excessive exercise and long-distance walking, avoidance of pain-inducing hip activities, rehabilitation, acupuncture, acupressure, physiotherapy, etc., and administration of non-steroidal analgesics and cartilage nutrients when necessary, as well as regular review. Surgery is needed if conservative treatment is not effective.