If the symptoms of osteoarthritis are very severe, medication is ineffective, and the patient’s daily life is affected, surgical intervention should be considered. For osteoarthritis of the knee, arthroscopic arthroscopic debridement is the first step, with minimal surgical trauma and rapid recovery. For most osteoarthritis, knee surface replacement surgery has a significant effect in relieving pain and restoring joint function. In case of severe pain and deformity, total knee arthroplasty is required, and the specific surgical methods are as follows: 1. Clean-up under direct vision is to remove the cartilage, meniscus, and fragments through the joint incision, and to grind the bone, degenerated meniscus, articular cartilage surface, and synovial membrane, and repeatedly flush the joint cavity to interrupt the inflammatory process, reduce symptoms and improve function. It is suitable for obese women over 40 years old, with swollen and painful joints, obvious bone redundancy at the edges of joints, free bodies in joints, relatively intact weight-bearing joints, and poor results of non-surgical treatment. 2. Arthroscopic debridement has both diagnostic and therapeutic functions, mainly including synovial debridement, joint surface repair, bone superfluous removal, release of adhesions, and repair of ruptured meniscus. Arthroscopic debridement is less invasive and quicker to recover after surgery, but it is not effective for those who have obvious damage to the knee joint and have deformed internal or external rotation angle. 3. Subchondral drilling is useful for those who suffer from joint pain and dysfunction caused by elevated intraosseous pressure and intraosseous stasis, and cartilage-like repair tissue is formed on the joint surface after surgery. 4. Osteotomy tibial high osteotomy is suitable for young patients and those with mild joint wear, tibial plateau bone collapse, not more than 0.5 em. The surgery is less damaging, can leave bed early, lower cost, and better near and long term results. 5. Knee fusion is suitable for young patients with severe osteoarthritis of the knee joint who are engaged in physical activities. 6. Artificial joint replacement is suitable for elderly patients with advanced KOA, more bone and joint destruction and severe pain. Artificial total knee joint surface replacement has developed rapidly in recent years, with a 10-year excellent rate of more than 90%. 7. Cartilage grafting is the transplantation of the distal femoral non-weight-bearing part of the intercepted bone column and autologous cartilage into the pre-treated cartilage defect tunnel on the surface of the knee joint. Smaller lesions can be repaired arthroscopically, while larger ones must be arthroscopically operated. Recently, frozen allograft cartilage has also been used with good results.