Introduction: Anterior cruciate ligament (ACL) injuries are common among Malaysian military patients but has not been studied closely. The purpose of this study was to assess the type of activities leading to the ACL injury and the outcome of reconstructive ACL surgery at one year follow up. Methods: From the registry record, military patients who had undergone ACL reconstruction in two Malaysian military hospitals were identified. Their medical records were reviewed. The activities that they performed when the ACL injury occurred were identified. After ACL reconstruction, the patients’ ability to resume previous duty at one year follow up was evaluated. Results: From 111 patients, 82% of the ACL injuries were due to sporting activities whereas military activities and road traffic accident accounted for 14 % and 4 % respectively. Out of 69 patients with isolated ACL injury who were followed up at one year, all except two were able to resume their previous duty. Conclusions: Among the military patients who underwent ACL reconstruction, ACL injury was mainly due to sporting activity. ACL reconstruction showed good outcome at one year follow up.