The goal of this study was to investigate the effects of simvastatin on the levels of plasma leptin and nitric oxide (NO) in patients with coronary heart disease (CHD). The study population consisted of 65 patients with CHD and 48 control individuals without signs or symptoms of CHD. The patients with CHD were treated with simvastatin 20mg/day. Fasting serum lipids, leptin and NO were determined before and after 12 weeks of treatment. Leptin levels were higher in patients with CHD than control (P<0.05). Statin treatment significantly decreased plasma lipids and leptin levels and increased NO concentration in all CHD patients (P<0.05). Serum leptin levels after treatment correlated negatively with the NO concentration (P<0.05). Simvastatin may provide beneficial effects of reducing leptin levels, independent of its lipid-lowering action, which may play an important role in patients with CHD.