The effect of capsaicin (0.02%) on the concentrations of liver and serum lipids, GOT and GPT activities, and hepatocyte morphology in male Sprague Dawley rats fed diets with or without erotic acid (1.0%) for 28 days was studied. Liver triglyceride concentration was increased by approximately 4.7-fold after erotic acid-feeding, wherease simultaneous feeding of capsaicin and erotic acid reduced its concentration by 38%. Orotic acidfeeding elevated liver cholesterol concentration, but an addition of capsaicin to the erotic acid diet resulted in the significant decrease in liver cholesterol. Capsaicin alone did not affect the liver triglyceride and cholesterol concentrations. Reduction of the serum concentrations of triglyceride and cholesterol by capsaicin was also observed in rats fed diets with erotic acid. The serum GOT and GPT activities were not significantly different among the experimental groups. Liver tissue morphology showed that the hepatocytes of erotic acid-feeding rats were a typical fatty liver with numerous fat droplets, whereas simultaneous feeding of capsaicin with erotic acid reduced the size and numbers of fat droplets. The present study demonstrated that the diet containing 0.02% capsaicin can prevent the erotic acid-induced fatty liver.