Objective: To assess bowel function and gastrointestinal quality of life among adults with operated Hirschsprung's disease (HD). Summary Background Data: Outcomes of HD extending to adulthood are unclear; bowel function and quality of life may deteriorate by aging. Methods: Bowel function and gastrointestinal quality of life were cross-sectionally assessed in a population-based manner among adults operated for HD during childhood between 1950 and 1986. Patients were interviewed during their outpatient visit. Controls matched for age and sex were randomly chosen from the Population Register Centre of Finland. Results: Ninety-two (64%) patients representative for the entire study population responded. The mean age of patients (79% male) was 43 (interquartile range [IQR], 35–48) years. Most (78%) had undergone Duhamel operation, and 94% had aganglionosis confined to the rectosigmoid. The mean overall bowel function score was decreased among patients (17.1 ± 2.8 vs 19.1 ± 1.2; P < 0.0001). They reported increased incidence of inability to hold back defecation (40% vs 17%), fecal soiling (48% vs 22%), constipation (30% vs 9%) and social problems related to bowel function (29% vs 11%; P < 0.05 for all). Gastrointestinal quality of life was only marginally lower among patients (121 ± 15.3 vs 125 ± 13.1; P = 0.0578) mainly because of significantly lower scores in questions assessing disease-specific factors such as bowel function and continence. Age was the only predictor of poor bowel function (OR 1.07, 95% CI 1.00–1.14, P = 0.049), which weakly predicted gastrointestinal quality of life (OR 0.81, 95% CI 0.66–1.01, P = 0.055). Conclusions: Although bowel function deteriorates with increasing age after operated HD, it is associated with only slightly decreased gastrointestinal quality of life.