The effects of preoperative selective arterial perfusion chemotherapy (PSAPC) in the treatment of 20 cases of histologically confirmed gastric cancers is reported in which 12 patients were operated on, and a comparison with that of general chemotherapy in 10 cases of gastric cancers (as controls) was made. In the PSAPC group, besides the improvement of clinical symptoms and singns, the cancer cells of lesions in situ and metastatic lymph nodes have different degrees of degeneration and necrosis. This result show significant differences in two group comparison (Plt;O.01). We conclude that the PSAPC has good short-term effect and little side-effect. It can improve the resection rate and radical resection rate, and prevent the iatrogenic metastasis and implantation during operation, and decrease the postoperative recurrence of the patients with gastric cancer.