PURPOSE:The purpose of this study is to evaluate the change of pancreatic size after gastric resection in patients with gastric malignancy. MATERIALS AND METHODS: We compared the pancreatic sizes on pre- and post-operative abdominal CT scans in 50 patients whose stomach had been resected due to malignancy. The mean interval was 20.3 months (range, 5-81 months). The types of the operation were total gastrectomy with esophagojejunostomy and jejunojejunostomy (n=7), and subtotal gastrectomy with gastrojejunostomy (Billroth II) (n=43). Pancreatic thickness was measured perpendicular to the pancreatic long axis at head, body and tail. RESULT: There was a significant reduction of pancreatic size on postoperative CT scan. The reduction rate was 5.9% in the head (p<0.001), 7.1% in the body (p<0.001) and 14.4% in the tail (p<0.001). CONCLUSION:Significant reduction of pancreatic size was observed after gastric resection due to gastric rnalignancy, especially in tail.