Abstract: Objective To explore the effect of resveratrol on the expression of bcl-2,bax gene in nude mice with implanted human primary gastric carcinoma cells with preventive administration of reserratrol. Methods The model of nude mice with the transplanted tumor was set up with the gastric cancer MGC-803 cell line.With preventive administration of resveratrol at low(50 mg/kg),moderate(100 mg/kg),and high dose(150 mg/kg),the effect of apoptosis in each group was observed with electron microscope and terminal deoxynucleotidyl transfernase-mediated nick end labeling(TUNEL) staining method.The expressions of mRNA and protein of bcl-2,bax gene were measured with reverse transcription PCR (RT-PCR)and immunohistochemical methods. Results Compared with the model group,the cell apoptosis was obvious in the groups with low,moderate and high does of resveratrol.The values of bcl-2/GAPD in the moderate and high dose groups were 0.26±0.072 and 0.24±0.083,respectively,lower than that of the model group(0.41±0.056,P<0.05).The values of bax/GAPD in the moderate and high dose groups were 1.31±0.11 and 1.47±0.089,respectively,higher than that of the model group(1.17±0.045,P<0.05).The expression of bcl-2 protein in the groups with resveratrol was obviously lower,but the bax protein was higher than those of the model group. Conclusion Resveratrol induces the apoptosis of implanted human primary gastric carcinoma cells in nude mice,and the mechanism may be related to the dow nregulation of the expression of bcl-2 gene and upregulation of the expression of bax gene.