Metallothionein-I (MT-I) gene was inserted into EcoRI site by using pSV2-neo plasmid vector. Recombiant plasmid was transfected into HeLa cells by DNA-calcium phosphate precipitation technique. MT-I expression colones were growing in medium including G418. The amount of MT-I expression in transfected cells was found 2.6 times higher than that of non-transfected ones. In order to observe the relationship between the expression of MT-I gene in cells and drug resistance, cells were treated with different concentrations of cisplatin and adriamycin respectively. The results indicated that cisplatin (0.1 mumol/ml) inhibited the growth of both transfected and non-transfected cells. The inhibitory rates were 34% and 82% respectively(P < 0.05). IC50(50% inhibitory concentration for cell growing) was 0.144 mumol/ml and 0.061 mumol/ml and the ratio of them was 2.36: 1 after the treatment of cisplatin 72 h later. The cells were treated with adriamycin 72 h later, the inhibitory rates of transfected and non-transfected cells were 18% and 25% separately. The rates showed no significant difference (P > 0.05). The results indicated that MT was related to drug resistance of tumor cells.