Objective To study the arthroscopy-assisted minimally invasive treatment of chondromalacia patella. Methods The clinical data of 140 patients with chondromalacia patella, with a mean age of 51.9 ± 5.71 years ( range, 41 to 62 years), undergoing surgical or Non-surgical treatment in our hospital from June 2005 to December 2008 were analyzed. In non-surgical group, 72 cases (96 knees) underwent intra-articular injection of sodium hyaluronate and other non-surgical treatment. In surgical group, 68 cases (84 knees) underwent variorus Arthroscopy-Assisted minimally invasive surgery, according to the extent of the patella cartilage injury and the situation of the patellofemoral joint. Joint functional exercise were carried out after operations. Regular follow-up were done after leaving hospital. Lysholm scoring system was used to evaluate the clinical effects. Judet's evaluation criteria was used to evaluate the improvement of range of motion. Results In non-surgical group, the knee function have been improved 24. 82%. In surgical group the knee function have been improved 35.37%. At the postoperative and final follow-up, the effect in surgery group was significantly better than non-surgical group. Conclusion For the chondromalacia patella with Ⅱ, Ⅲ class cartilage injury, minimally invasive arthroscopic surgery is a good treatment method, which can reduce pain, improve function, slow down the progress of the disease, and improve the quality of life of patients.