Background We aimed to evaluate the characteristics of hospitalizations for radiation proctitis (RP). Methods The National Inpatient Sample (NIS) was analyzed to identify RP hospitalizations for 2016 and 2017. Outcomes included mortality, predictors of mortality, mean length of stay (LOS), mean total hospital cost (THC), and numerous system-based complications. Results We identified 16,810 adult hospitalizations for RP. On admission, an initial diagnosis of RP was established for only 27.54% of these patients. The mean age was 72.3±0.5 years and 30.2% of the study population was female. Whites made up 68.7% of the study population. Most hospitalizations for RP were at large (51%), urban (93.6%), and teaching (71.1%) hospitals. The inpatient mortality for RP hospitalizations was 1.7%. After adjusting for biodemographic factors, hospitalization characteristics and comorbidities, older age and protein energy malnutrition (PEM) were associated with higher odds of inpatient mortality. The mean LOS and THC for RP hospitalizations were 5.6 days and $53,800, respectively. Inpatient complications associated with RP included acute renal failure (19.7%), sepsis (4.4%), deep vein thrombosis (3.7%), acute respiratory failure (3.3%), and pulmonary embolism (0.7%). Conclusions Inpatient mortality for RP was 1.7%. Older age and PEM were associated with higher odds of inpatient mortality.