Cytotoxicity of glucose oxidase(GO) and cardioprotective effect of Salviae Multiorrhizae Radix(SMR) against GO-induced cardiotoxicity were measured for evaluation of cardiotoxicity on cultured mouse pulmonary endotherial cells(PEC) by MTT assay after PEC were cultured for 8 hours at various concentrations of GO. GO was toxic in a time and dose-dependent manner on cultured PEC after PEC were grown for 8 hours in media containing 1～60mU/ml GO. While, cultures were pretreated with 60 μg/ml SMR for 2 hours increased remarkably cell viability. From the above results, it is suggested that GO is toxic on cultured PEC by the decrease of cell viability, and herb medicine such as SMR is very effective in the prevention of vascular toxicity induced by GO.