In order to analyse the role of the spleen on immunosuppression of gastric cancer, T cell phenotypes in the spleen cells (SC) were investigated by two colour fluorescence flow cytometry, with reference to their suppressor cell activity. Suppressor T cell phenotypes of CD4+2H4+ cells (suppressor/inducer T cells) and CD8+CD11+ (suppressor T cells) were distributed predominantly in SCs from patients with gastric cancer, while they were distributed scarcely in those with liver cirrhosis. Moreover, CD4+2H4+ cells and CD8+CD11+ cells were found predominantly in SCs and splenic vein lymphocytes (SVL) respectively. Among SCs, a significantly higher proportion of CD4+2H4+ cells was found in the recirculating SCs, but fewer were found in the residual SCs. Higher activity of Concanavalin-A induced suppressor cells was found in the former and that of spontaneously activated suppressor cells was found in the latter. These results suggest the suppressor precursor and suppressor/inducer T cells might distribute predominantly in the cells recirculating from the spleen, and that suppressor cells might be matured during the migration from the spleen.