Objective To study the effect of evodiamine（Evo） on human gastric adenocarcinoma cell line（SGC-7901） and discuss the mechanism.Methods The anti-tumor activity of Evo was determined by using MTT assay

and the influence of Evo on morphological changes was observed with the transmission electron microscope（TEM）.The influence of Evo on the electrophoretic behavior of DNA was detected by using agarose gel electrophoresis

and the inhibitory effect and influence of Evo on SGC-7901 and cell cycle were detected by using flow cytometry.Results Evo

in a certain concentration

had a dose-time-dependent inhibitory effect on the proliferation of SGC-7901.The results of TEM showed nucleus chromatin margination

nuclear fragmentations and apoptotic bodies.Evo

in a certain concentration

brought cell genome DNA out ladder bands.The outcomes of flow cytometry showed that the cells of G0/G1 phase and S phase decreased

a lot of cells arrested in G2/M phase

and apoptotic cells increased.Conclusion The inhibitory and apoptosis-induced effects of Evo on SGC-7901 are closely related to that it can induce the apoptosis and bring the cells arrest in G2/M phase.