One hundred and thirty three gastric cancer cases were investigated immunohistochemically to clarify the biological role of survivin in gastric cancer cells using a commercially available anti-survivin antibody (SURV11A). Five gastric cancer cell lines were employed to assess localization of survivin by reverse-transcription-polymerase chain reaction (RT-PCR) Southern blotting, Western blotting and immunofluorescence, signals being found in both nucleus and cytoplasm. Survivin nuclear staining of gastric cancer cells was evident in 109 of 133 cases (82.0%) and associated with a favorable prognosis, being an independent prognosticator on multivariate analysis. Survivin nuclear positivity also correlated with younger age and lower incidence of vessel cancer invasion. In contrast, survivin cytoplasmic positivity was noted in 117 cases (88.0%) and did not correlate with any factor of progression or prognosis. The results indicate that survivin is present in the majority of gastric cancer cells but a nuclear localization may play an important physiological role in hindering tumor progression.