Objective To explore the effects of early adminstering various doses of atorvastatin on serum sCD40L level and prognosis in patients with acute coronary syndrome (ACS). Methods One hundred and sixty-eight patients with ACS were randomly divided into three groups, which were administered atorvastatin at the dose of 10mg/d (low-dose group, n=56), 40mg/d (middle-dose group, n=55) and 80mg/d (high-dose group, n=57), respectively. Levels of serum sCD40L and lipid before and after treatment were measured. The major adverse cardiovascular events (MACE) were followed up for mean 7.6?3.2 months. Results The levels of serum sCD40L had no significant changes before and after treatment in low-dose group, but significantly reduced 52.4% and 52.2% in high-dose group and middle-dose group after treatment (P