Background: Mitral valve (MV) repair offers potential advantages over replacement in patients with rheumatic heart disease (RHD). We present the first long-term study that compares MV repair with replacement in children with RHD. Methods and Results: Single institute retrospective review of patients with RHD under 20 years of age, who underwent their first isolated MV surgery between 1990 and 2006. Of the 81 patients, 98% were Māori or Pacific Islander. The median age was 12.7 (3-19) years. The MV was repaired in 59%, a mechanical valve replacement (MVR) took place in 35% and bioprosthetic valve replacement in 6% of the patients. Follow-up data were available for 91.4% of the patients with mean follow-up of 7.6 years (range 0-19.4 years), a total of 620 patient years. Actuarial survival at 10 and 14 years for patients with MVR was 79% and 44%, compared to 90% and 90% for patients who underwent repair ( P = .06). Actuarial freedom from late reoperation at 10 and 14 years for patients with MVR was 88% and 73%, compared to 76% and 76% for patients with repair ( P = .52). Actuarial freedom from thrombotic, embolic, and hemorrhagic events at 10 and 14 years for patients with MVR was 63% and 45%, compared to 100% and 100% for patients with repair P < .01). Conclusion: This study shows that MV repair is superior to replacement for RHD in the young with follow-up to 19 years. Repair offers a survival advantage, greater freedom from valve-related morbidity, and long-term durability that equals that of MVR.