Effects of subchronic aluminum （Al） exposure on the function of rat liver were investigated in this experiment. A total of 48 male Wistar rats （4 weeks old） were randomly divided into four groups： experimental groups were orally exposed to 64.18, 128.36, 256.72 mg. kg^-1 body weight aluminum trichloride （AlCl3） in drinking water, and the control group with distilled water. The experiment lasted for 120 days. The activities of superoxide dismutase （SOD） and glutathione peroxidase （GSH-PX）, the concentration of malondialdehyde （MDA） in serum and liver, and alanine transarninase （ALT） and aspartate aminotransferase （AST） activities in serum were detected in all groups. The results showed that the activities of ALT, AST in serum and the concentrations of MDA in liver in the Al-treated groups significantly increased compared with the control group; the activities of GSH-PX and SOD in high-dose Al-treated group were significantly lower than those in control group. Our findings indicated that subchronic AI exposure could result in injures of lipid peroxidation and function in liver.