Objective: To observe the therapeutic effects of arthroscopic treatment for recurrent patellar dislocation by anatomical reconstruction of medial patellarfemoral ligament., Methods: From June 2009 to December 2014, 25 patients with recurrent patellar dislocation were treated with anatomical reconstruction of medial patellarfemoral ligament surgery under arthroscopy. There were 10 males and 15 females, with an average age of 18.4 years old (ranged, 15 to 25 years old ). There were 15 patients who had a medical history of sports injury, 7 patients had a chronic impairment history, and the other 3 patients had the symptoms without obvious predisposing causes. Fourteen patients had injuries on the right knee and 11 patients had injuries on the left knee. All the patients suffered from patellar dislocation 3 to 10 times. After operation, the exercise of knee joint were performed postoperatively. The knee range of motion, Lysholm score, Kujala score, Insall criteria, Patellar apprehension test and patellar grinding test were observed to evaluate the clinical effects., Results: All the patients were followed up, and the duration ranged from 12 to 48 months, with an average of 24.8 months. After surgery, all the wounds were healed excellent and there were no complications like surgical incision infection or patellar redislocation. The ranges of motion was increased from preoperative (105.40±5.93)° to postoperative(122.60±5.42)°. At the latest follow-up, the Lysholm scores were increased from preoperative 64.12±7.49 to postoperative 91.44±5.53, the Kujala scores were increased from preoperative 57.88±5.10 to postoperative 92.44±2.69. According to the Insall criteria, 19 patients got an excellent result, 5 good and 1 fair., Conclusions: It has a satisfactory clinical therapeutic effect on anatomical reconstruction of medial patellarfemoral ligament under arthroscopy for the treatment of recurrent patellar dislocation. It is helpful for the relief of clinical symptoms and improvement of knee joint function., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose.