Abstract: Objective :To evaluate the effect of postoperative introperitoneal chemotherapy and the relationship between intraperitoneal chemotherapy (IPC) and biological behavior of gastric cancer. Methods : Two hundred and seventy-five cases of gastric cancer were divided into the test team (128 cases) and the contrast team (147 cases) due to IPC or not. in test team, 43℃ saline 1000ml+5-Fu 750mg+CBP 400mg or DDP 40～50mg are dripped into the peritoneal cavity of each patient every two weeks, totally 2～4 times. The patients of contrast didn't have IPC. The Kaplan-Meier survival curve was used to analyze the difference of the survival time between the test team and the contrast team and χ2 test was used to evaluate the effect of IPC in the same type of biological behavior. Results : The Kaplan-Meier survival curve analysis showed that IPC prompted the 1-year survival rate (13.8%) and the 3-year survival rate (20.5%) of test team contrary to the contrast team after radical operations. The median survival time was prompted from 30 months to 52 months. IPC prompted the survival time of the cases who have poor biological behavior of gastric cancer. Besides, IPC prolonged 8 months for the median survival time the median survival time 8 months in the cases who had palliative operations. Conclusion : IPC is an effective postoperative adjuvant treatment to advanced gastric cancer.