BACKGROUND: With advances in medical care, patients with cystic fibrosis are more commonly living into adulthood, yet there are limited data describing the need for GI surgery and its outcomes in adult cystic fibrosis patients. OBJECTIVE: We aim to use a national administrative database to evaluate trends in abdominal GI surgery and associated postoperative outcomes among adult cystic fibrosis patients. DESIGN: This was a national retrospective cohort study. SETTING: A national all-payor administrative database from 2000 to 2014 was used. PATIENTS: Patients included adults (age ≥18 years) with cystic fibrosis undergoing abdominal GI surgery. MAIN OUTCOME MEASURES: The primary outcome was trend over time in number of surgical admissions. Secondary outcomes included morbidity and mortality by procedure type. RESULTS: We identified 3075 admissions for abdominal surgery, of which 28% were elective. Major GI surgical procedures increased over the study period (p < 0.01), whereas appendectomy and cholecystectomy did not demonstrate a clear trend (p = 0.90). The most common procedure performed was cholecystectomy (n = 1280; 42%). The most common major surgery was segmental colectomy (n = 535; 18%). Obstruction was the most common surgical indication (n = 780; 26%). For major surgery, in-hospital mortality was 6%, morbidity was 37%, and mean length of stay was 15.9 days (SE 1.2). LIMITATIONS: The study is limited by a lack of granular physiological and clinical data within the administrative data source. CONCLUSIONS: Major surgical admissions for adult patients with cystic fibrosis are increasing, with the majority being nonelective. Major surgery is associated with significant morbidity, mortality, and prolonged length of hospital stay. These findings may inform perioperative risk for adult patients with cystic fibrosis in need of GI surgery.