Lymph node (LN) dissection along the upper border of the pancreas is one of the essential parts of curative surgery for gastric cancer, and the distal portion of the pancreas was frequently resected for complete removal of LNs along the splenic artery. However, pancreatic juice leakage, subphrenic abscess, and postoperative diabetes were common complications in patients treated by pancreatic resection. To avoid these problems a new surgical procedure, the pancreas-preserving operation, was developed by Maruyama in 1979. We found that lymphatic channels from the stomach did not flow into the pancreas parenchyma, and that the spleen, splenic artery, and fatty connective tissue including nodes could be removed completely without dissection of the pancreas parenchyma and splenic vein. The preserved pancreas receives its arterial blood supply through the transverse pancreatic artery, and its preservation prevents postoperative diabetes. A total of 299 patients were treated by this procedure. The operative mortality rate was 0.3%, the hospital death rate 1.6%, and the surgical complications rate 19.6%. The cumulative 5-year survival rate for those with stage II was 70.5% and for those with stage III 54.1%. These results were superior to those of the pancreas resection group.