PURPOSE: The aim of this study was to analyze the causes of failure after a primary anterior cruciate ligament reconstruction (ACLR), associated injuries, and the clinical results of revision ACLR. MATERIALS AND METHODS: This study evaluated 46 patients (46 knees), who were followed at least two years after revision ACLR. The evaluations included the causes of failure after primary ACLR, associated injuries, 2000 International Knee Documentation Committee (IKDC) subjective knee scores, Lachman test, Pivot shift test, and KT-1000 arthrometer measurement. RESULTS: The most common cause of failure was trauma (27 patients, 58.7%) and 19 failures (19 patients, 41.3%) were caused using an inappropriate surgical technique. The associated injuries were meniscus tears in 29 cases (63.0%) and articular cartilage injuries of Outerbridge grade II to IV in 19 cases (41.3%). The IKDC scores, Lachman test, Pivot shift test, and KT-1000 arthrometer measurements were improved significantly at the final follow-up. CONCLUSION: The most common cause of failure after primary ACLR was trauma. One stage revision ACLR resulted in relatively satisfactory stability but less satisfactory clinical function than the primary reconstruction, as reported previously, which is believed to be due to the more associated injuries.