Objective — to improve the results of treatment in patients with locally advanced and disseminated gastric cancer, by applying a procedure for hyperthermic intraoperative intraperitoneal chemotherapy (HIIC). Material and methods. Thirty surgical interventions using a HIIC procedure were performed in 2010 to 2014. Locally advanced gastric cancer (T3—T4) without visual signs of peritoneal carcinomatosis was observed in 22 cases; 4 patients of them were found to have free abdominal cancer (Cyt+) cells by emergency immunocytochemical examination of peritoneal lavages. A group of patients with disseminated gastric cancer included two subgroups according to the extent of dissemination. Circumscribed peritoneal carcinomatosis (P1) was noted in 4 cases; disseminated P2—P3 was diagnosed in 4 patients. Results. Median survival was 30 months in the locally advanced gastric cancer group. In the Cyt+ subgroup, 2 of the 4 patients died; however, there was a considerable increase in the recurrence-free period up to 30 months. In the disseminated gastric cancer group, 2 patients are currently alive; two with the similar extent showed an increase in the recurrence-free period up to 14 months. In the P2—3 subgroup, all the 4 patients died from progressive disease at 4 to 10 months after intervention with HIIC. Conclusion. Circumscribed peritoneal dissemination, free abdominal cancer cells, and massive tumor access to the serosa in gastric cancer can be regarded as an indication for HIIC. In gastric cancer with disseminated carcinomatosis, the efficiency of HIIC is questionable even if there is complete cytoreduction, the process progresses in the majority of patients immediately after surgery.