Purpose To compare the clinical outcomes of meniscus repair and meniscus resection with concurrent anterior cruciate ligament (ACL) reconstruction in patients with ACL rupture and neglected or delayed medial meniscus tears. Methods Thirty patients with ACL ruptures and unstable vertical longitudinal medial meniscus tears were included. Patients were divided into two groups. Group I included 15 patients who underwent meniscal repair and Group II included 15 patients who underwent meniscectomy. The knee range of motion, McMurray test, Lachman test, pivot shift test, Lysholm Knee Scoring Scale, International Knee Documentation Committee (IKDC) Questionnaire, Hospital for Special Surgery (HSS) Knee score, and Tegner activity (TA) scale were used to assess all patients. Results The median follow-up time was 3.6 (0.5-6.5) years. Median age was 28 (16-36) years. Fourteen patients (93.3%) in Group I and six patients (40%) in Group II returned to their preinjury sport activity level (P = .007). Median maximum knee flexion was 132 degrees (121 degrees-140 degrees) in Group I and 134 degrees (121 degrees-139 degrees) in Group II (n.s.). All patients had full knee extension and negative McMurray test results. Lachman and pivot shift test results were similar between groups. The median IKDC Questionnaire score was 99 (86-100) in Group I and 93 (70-100) in Group II (P = .016). The difference in Lysholm Knee Scoring Scale, HSS knee, and TA scale score between groups were not significant. Conclusion Clinical outcomes of patients that underwent meniscus repair were better than those that underwent meniscus resection with concurrent ACL reconstruction. The technically complicated and costly meniscus repair may achieve better clinical outcomes than meniscectomy when treating a neglected or delayed meniscal tear with a concurrent ACL tear.