Objective: Anterior cruciate ligament injury is one of the commonest ligament injuries of knee joint. Arthroscopic acl reconstruction is indicated if patient presents with knee instability and wants to get back to active life style. Incidence of meniscal and chondral injuries is high in chronic acl injured knees .There is still debate on ideal acl reconstruction graft choice, graft fixation methods and tunnel making techniques. So we conducted an observational study on functional evaluation of arthroscopic acl reconstruction using single bundle of quadrupled hamstring graft fixed with endobutton at femoral side and with interference screw at the tibial side using transportal technique. Materials and methods: Arthroscopic acl reconstructed adult patients less than 60 years were included in the study. Those acl injuries in children and older patients with osteoarthritic changes and associated bony injury patients were excluded from the study. Results: There were 40 cases in the study with age ranging from 20 to 47 years with mean age of 31 years. Sports was the most common mode of injury. Isolated acl injury was found in 62.5 percent of cases and combined meniscus injury along with acl injury was found in 37.5 percent of cases in the study. Partial menisectomy was done in 90 percent of cases while meniscus repair was done in 10 percent of cases. The time period from injury to surgery varies from one week to one year with mean time of 3 months. Patients were followed up for a minimum period of one year and evaluated with Lysholm score. The maximum score achieved was 95 and minimum score was 71. There is statiscal significance between pre and postoperative lysholm scores and between associated knee injures and lysholm score. All patients were able to return to their previous job at four months. Conclusion: Arthroscopic Acl reconstruction with quadrupled hamstring graft fixed at anatomical site with endobutton at femoral side and with interference screw at tibial side leads to reproducible good functional results with minimum morbidity and helps patients get back to their previous job. Keywords: arthroscopic acl reconstruction, hamstring tendon, endobutton