To study the effect of intraperitoneal hyperthermic double distiled water and cis-diamminedichloro-platinum(DDP) perfusion to the peritoneal cancerous ascites,intraperitoneal injection of H22 cancer cells (2×107 tumor cell,each mouse) were performed in LACA mice. Five days after cancer cells injection, intraperitoneal perfusion of simple hypertherrnic (43℃) double distiled water(group Ⅰ) isotonic fluid (group Ⅱ ). DDP (group Ⅲ ), and hypertherrnic double distiles water perfusion combined with DDP (guoup Ⅳ ) were performed .The results showed that cancer cells in the peritoneal cavity of LACA mice were seriously damaged, the production of ascites was markedly inhibited and the survival days of LACA mice were prolonged in all groups . .The intraperitoneal hyperthermic double distilled water perfusion with DDP group showed more effective result as compared with the other groups,Only 1 peritoneal implanted dissemination was found after treatment in this group,Basing on the experimental from September 1991 through September 1993,intraperitoneal hyperthermic double distiled water perfusion with DDP was used to treat 32 advanced gastric cancer patients after radical gastrectomy with satisfactory results.