A 26-year-old woman with an eating disorder presented to the emergency department with severe abdominal pain following binge eating. A plain film X-ray demonstrated a huge dilatation of the stomach with a high air-fluid level. Serum amylase was 2,265 IU/L, and serum lipase was 2,001 IU/L. Abdominopelvic computed tomography scan revealed a massive gastric dilatation and completely compressed duodenum. The distended right colonic loop and small bowel loops were reduced to the pelvic area and the displaced small bowel and mesenteries tightly pulled on the mesenteric vasculature. After nasogastric tube decompression and irrigation, her abdominal pain subsided. On the 15th day after admission, a follow-up abdominopelvic computed tomography scan demonstrated mild edematous changes of the pancreas compatible with pancreatitis.