Possible causes of knee pain include osteoarthritis, rheumatoid arthritis, septic arthritis, etc. Treatment can be divided into conservative treatment and surgery. 1. Osteoarthritis: Osteoarthritis can be treated conservatively in the early stage, including rest, avoiding weight bearing, heat application, physiotherapy, etc. Some medications such as Celecoxib and Glucosamine can also be used. Surgery can be considered if conservative treatment is not effective. Arthroscopic surgery, osteotomy, arthroplasty, etc. can be chosen according to the condition. 2. Rheumatoid arthritis: The treatment of rheumatoid arthritis is also divided into conservative treatment and surgery. Conservative treatment measures are similar to those of osteoarthritis, but some anti-rheumatic drugs can be used to slow down the progress of the disease, such as methotrexate, cyclosporine and so on. Surgical treatment can be considered if the indications for surgery are met, including arthroscopic subluxation, arthroplasty and so on. 3. Septic arthritis: Early treatment with adequate antibiotics, commonly used drugs include cephalosporin and levofloxacin. Local braking can help control infection, relieve muscle spasm and prevent joint deformity. In addition to systemic anti-infection treatment, arthrocentesis and irrigation should be performed to remove the infected foci in the joint cavity. If the condition does not improve with the above treatments, incision and drainage are needed, followed by antibiotic injection. In addition to the above diseases, knee tuberculosis, meniscus or ligament injury, knee bone tumor can cause knee pain, it is recommended to go to the hospital as soon as possible to improve the relevant examination, timely identification of the cause, and follow the doctor’s instructions to be targeted treatment, do not blindly use their own medication, so as not to cause adverse consequences.