Background: The aim of this study was to review our institutional experience with patients who underwent surgical repair of aortopulmonary window, either as an isolated lesion or in association with other cardiac anomalies. Methods: Between January 2006 and December 2020, 183 patients underwent surgical repair of aortopulmonary window at our institute. Sixty-three patients had associated lesions (Group 1); 120 patients had isolated aortopulmonary window (Group 2). Median age was 7 months. Results: The early mortality in Group 1 was significantly higher (12.7%) compared to Group 2 (0.8%) ( P = .001). The most common associated anomaly was ventricular septal defect (29 patients). On univariable analysis, cardiopulmonary bypass time ( P < .001), aortic cross-clamp time ( P < .001), delayed chest closure ( P = .02), sepsis ( P = .006), tracheostomy ( P = .002), extracorporeal membrane oxygenation ( P < .001), associated lesions ( P = .001), pulmonary artery hypertensive crisis ( P < .001) were predictors for early mortality. On multivariable analysis only pulmonary artery hypertensive crisis was identified as predictor for early mortality ( P = .03; odds ratio = 24). Survival at both 5 years and 8 years was 77% ± 6.5 in Group 1 and 98.8% ± 1.2 in Group 2 ( P≤.001). Freedom from reintervention at both 5 years and 8 years was 92.4% ± 5.2 in Group 1 and 100% in Group 2 ( P = .055). Conclusion: Early outcomes of aortopulmonary window repair are excellent among patients in which this is an isolated lesion, as compared to those with associated lesions. Long-term outcomes in terms of freedom from reoperation are excellent in both the groups.