BACKGROUND Gastrointestinal complications after lung transplatation are associated with an increased risk of morbidity and mortality. This study aims to describe severe gastrointestinal complications (SGC) after lung transplantation. METHODS We performed a prospective, observational study that included 136 lung transplant patients during a seven year period in a tertiary care universitary hospital. SGC were defined as any diagnosis related to the gastrointestinal or biliary tract leading to lower survival rates or an invasive therapeutic procedure. Early and late complications were defined as those occurring < 30 days and ≥ 30 days post-transplant. The survival function was calculated through the Kaplan-Meier estimator. Variables were analyzed using univariate and multivariate analysis. Statistical significance was defined as p < 0.05. RESULTS There were 17 (12.5%) SGC in 17 patients. Five were defined as early. Twelve patients (70.6%) required surgical treatment. Mortality was 52.9% (n = 9). Patients with SGC had a lower overall survival rate compared to those who did not (14 vs 28 months, p = 0.0099). The development of arrhythmias in the first 48 h of transplantation was a risk factor for gastrointestinal complications (p = 0.0326). CONCLUSIONS SGC are common after lung transplantation and are associated with a considerable increase in morbidity-mortality. Early recognition is necessary to avoid delays in treatment, since a clear predictor has not been found in order to forecast this relevant comorbidity.