Abstract: The preventive effects of Zn Glycyrrhizate (Gly-Zn) on lethal toxicity, nephrotoxicity, hemotoxicity, testicular toxicity and anticancer activity of cisplatin (CDDP) were investigated in mice. The toxicity of CDDP evaluated by the above criterion was significantly reduced by preadministration of Gly-Zn 400 mg·kg^-1·d^-1×5(P<0.05 or P<0.01). The protective effects were better than bismuth subnitrate (BSN) which has been studied previously (0.05<P<0.1). The metallothionein (MT) level in the liver, kidney, heart and cancer of mice treated with one of these compounds were determined. The results showed that the levels of MT induced by Gly-Zn were significantly increased in liver and kidney (P<0.05). It was just in conformity with the conclusion that the best protective effect appeared in the groups treated with preadministration of Gly-Zn. These results suggest that increased MT synthesis in the liver and kidney may be involved in the protective effect of Gly-Zn on the toxicities produced by CDDP. The experiments also showed that Gly-Zn did not affect the anticancer effect of CDDP in vitro and in vitro, while the MT level was not increased in cancer (P<0.05), so Gly-Zn might improve the therapeutic index of CDDP.