Repeated intraperitoneal chemotherapy (RIC) via i.p. port was carried out in 16 patients with peritoneal dissemination P(+) and 8 with positive washing cytology P0.cy (+). CDDP with/without MMC soluted by physiological saline was periodically administered via i.p. port. The average administration was 5.6 times (2-16, median: 6) and the average dose was 288.0 mg. As the results, negative change of washing cytology after RIC was found in 71%, with a high rate especially in P0.cy (+) cases. Also, median survival time (MST) of responders was statistically longer than that of non-responders (777 days vs 254 days). Although diarrhea and anorexia of grade 3 developed once in each one patient, serious toxicities were not found. In conclusion, RIC is effective for peritoneal dissemination, especially P0.cy (+) cases, from gastric carcinoma.