Aim To investigate the differences of 40 mg versus 10 mg atorvastatin on the levels of serum prostacyclin and platelet activation in patients with ischemic cardiomyopathy (ICM).Methods 77 patients with ICM in the Department of Cardiology were recruited to this study from March 2008 to June 2010. Patients were randomly divided into two groups: 10 mg/d atorvastatin group (n38) and 40 mg/d atorvastatin group (n39). All subjects were followed up for 1 year. The levels of serum glutamic-pyruvic transaminase, creatine kinase, lipids, platelet, platelet activating factor (PAF), 6-keto-prostaglandin F1α(6-Keto-PGF1α) and thromboxane B2 (TXB2) were examined in all subjects at baseline and at the end of study. The incidences of adverse reactions in two study groups were taken down.Results At the end of this study, the levels of serum total cholesterol, low density lipoprotein cholesterol, TXB2, TXB2/6-Keto-PGF1α, PAF were significantly decreased and 6-Keto-PGF1α were significantly increased in 40 mg/d atorvastatin group in comparison with 10 mg/d atorvastatin group (P<0.05). There were no significant differences between the two groups on the levels of serum glutamic-pyruvic transaminase, creatine kinase, platelet and the incidences of adverse reactions for medicines.Conclusions 40 mg/d atorvastatin might significantly decrease the levels of platelet activation and increase the levels of serum prostacyclin in patients with ICM in comparison with 10 mg/d atorvastatin.