Abstract: AIM: To study the antitumor effects of losartan in EAC mice. METHODS: The inhibitory rates of tumor growth and the ratio of extending viability were observed in EAC mice in three groups given losartan, 5- FU and NS, respectively. RESULTS: Comparing with the control groups, the inhibition to tumor growth was 46.3 % in losartan (12.5 mg·kg ^-1) group.But losartan did not lengthen life time in EAC mice.The inhibition to tumor growth was was 31.5 % in 5-FU (5 mg·kg ^-1) group. CONCLUSION: Losartan can inhibit the tumor growth of EAC, but not lengthen life time of the animals.

Key words: pharmacology, losartan, 5-FU, EAC, antitumor effect