Abstract: To study the toxic mechanism of lead and prevent or treat the toxicity of lead,the effects of lead on lipid peroxidation(LPO)of most organs,some biochemistry indices of serum and the concentrations of Pb and Ca in most organs of the mice after intravenous injection by Pb(CH₃COO)₂ were studied.The results showed that the LPO of liver,kidney,brain,spleen and testes of the exposed groups were significantly higher than those of the controls,the activity of aspartate aminotransferase(AST),alanine aminotrans-ferase(ALT)and lacatate dehydrogenase(LDH)in serum and concentrations of Pb and Ca in most organs of mice were also significantly changed.These results suggested that lipid peroxidation maybe one of the mechanisms of lead toxicity.