Objective:To investigate the effect of fascin 1 on proliferation and apoptosis in gastric cancer cell line MKN45. Methods :RNA interference (RNAi) was used to inhibit fascin 1 expression in human gastric cancer cell line MKN45. Expression of fascin 1 was examined by western blotting and RT-PCR. Cell growth ability was evaluated by MTT and clone formation assays. Cell apoptosis was examined by flow cytometry and Hochest 33258 staining method. Results:Knockdown of fascin1 expression in MKN45 cells resulted in decreased cellular proliferative ability, but not apoptosis. The cloning efficiency of cells transfected with small interfering RNA(siRNA) was significantly lower [(36.5±8.1)%] as compared to that in MKN45(79±6.3)% (P<0.05). Conclusions:Expression of fascin 1 is related to the proliferation of gastric cancer cell line MKN45, but has no significant relationship to apoptosis.