Objective To compare the functional outcomes of anterior cruciate ligament (ACL) reconstruction with hamstring autograft (HA) through the all-inside (AI) technique with adjustable-loop cortical Endobutton (Smith & Nephew, Watford, Hertfordshire, England) on the sides of the femur and tibia and through the outside-in (OI) technique using an interference screw on the tibial side and a cortical Endobutton on the femoral side. Materials and Methods The present is a double-blinded randomized controlled trial (RCT) of 44 patients undergoing arthroscopic ACL reconstruction from February 2019 to February 2022 in a tertiary care hospital. As per computer-based randomization, the patients were distributed into two groups: the AI and OI groups. Both groups were evaluated for 12 months using the Visual Analog Scale (VAS), the Lysholm Knee Scoring Scale, and part I (pain score) and part II (function score) of the Knee Society Score (KSS). Results On postoperative day 2, the VAS score was significantly higher in the OI group ( p = 0.0001), but insignificant ( p = 0.807) at 6 weeks. At 3, 6, and 12 months of follow-up, the score on the Lysholm Knee Scoring Scale was significantly higher ( p = 0.001) in the AI group. At 6 months, both parts of the KSS showed a significant difference, with the AI group presenting a better outcome ( p = 0.04). However, at 12 months, the AI group presented a better score on part I of the KSS, but no differences were observed regarding part II. Conclusion In a follow-up of 12 months, the patients submitted to the AI technique presented better outcome scores and pain relief than those submitted to the OI technique.