To investigate the effects of Huangqi Jiedu Decoction on proliferation, apoptosis and C-myc gene expression of gastric cancer SGC-7901 cells. Methods:SGC7901 gastric cancer cells were intervened respectively with Huangqi Jiedu Decoction concentrate (experimental group) and adriacin solution (positive control group), and SGC7901 cells without any drug treatment were for control group. MTT assay and flow cytometry were used to detect the proliferation and apoptosis of SGC7901 cells, C-myc gene expression in cells was detected by RT-PCR. Results:The inhibitory rate of cell proliferation in experimental group and positive control group increased with the prolongation of culture time (P<001), and the inhibition rate of cell proliferation in experimental group 48 hours and 72 hours after cell culture was higher than those in positive control group (P<005). The apoptosis rate of experimental group and positive control group was significantly higher than that of control group (P<001), but there was no significant difference between experimental group and positive control group (P>005). The relative expression of C-myc mRNA in control group, experimental group and positive control group were （169±063）,（068±037）,（086±028） respectively. The relative expression of C-myc mRNA in experimental group and positive control group was lower than that in control group (P<001), and experimental group was lower than positive control group (P<005). Conclusion:Huangqi Jiedu Decoction can effectively inhibit the proliferation and promote the apoptosis of gastric cancer SGC-7901 cells, which may be related to the down-regulation of C-myc gene expression.