The influence of proliferation and proliferation kinetics on prognosis in gastric cancer after complete resection are controversial. In a prospective study we investigated the tumour specimens of 111 patients after resection of gastric cancer, who received 200 mg intravenous (i.v.) bromodeoxyuridine (BrdU) pre-operatively. The following biological parameters were analysed in the tumour tissue using flow-cytometry: DNA ploidy, proportion of S-phase cells, BrdU labelling index (LI), DNA synthesis time (T s ), potential tumour doubling time (T pot ), proliferating cell nuclear antigen (PCNA) and Ki-67 LI. The median follow-up time was 40 months (range 19–62 months). Besides the established pathohistological prognostic factors, univariate analysis revealed a prognostic influence on survival for BrdU LI, T pot and the proportion of S-phase cells. By multivariate Cox analysis of the completely resected cases, only tumour stage and T pot had a significant, independent influence on survival. By classification and regression trees (CART) analysis, resection status, tumour stage and T pot defined risk groups with significantly different outcomes. A short T pot was a predictor of better survival in stage I, II and IIIA tumours. Ploidy and the other investigated proliferation-related parameters failed to demonstrate any influence on prognosis after resection of gastric cancer.