The effect of taurine on serum and liver cholesterol level in rats and its mechanism was investigated. Female weanling SD strain rats (80-100 g) were divided into four groups, eight rats in each group. Group A fed with normal diet. The diet of groups B, C and D was normal diet incorporated with taurine at the levels of 6, 13.5 and 30 g/kg diet respectively. The experiment lasted for five weeks. Results showed that the blood cholesterol levels of rats with diets containing taurine were decreased. The decrease of plasma total cholesterol(TC), low density lipoprotein-cholesterol in the 6 g/kg taurine group was the most significant. Plasma triglycerides and apolipoprotein(Apo)-B in the 13.5 g/kg taurine group was decreased, and the amount of fecal bile acids was increased in this group. Plasma Apo-AI of the 30 g/kg taurine group was increased and the liver TC was decreased.