We compared the effects of capsinoid, a non-pungent component, on serum and liver lipids, with that of synthetic capsaicin in hyperlipidemic rats. Male Wistar rats of 9 wk old were divided into 4 groups: a control group receiving a high-fat diet containing 1% cholesterol, and capsaicin, capsinoid-I and capsinoid-II groups supplemented with 0.1 mmol of N pelargonylvanillylamide (synthetic capsaicin), and 0.1 mmol and 1.0 mmol of capsinoid (capsiate: dihydrocapsiate=63:37) per kg of control diet, respectively. All groups were pair-fed for 4 wk. Compared with the control group, serum lipid levels in both capsinoid groups and liver lipid contents in the capsinoid-II group showed the same reduction as that of the capsaicin group. In the capsaicin and capsinoid-I groups, fatty acid synthase (FAS) activities were lower and hepatic triacylglycerol lipase (HTGL) [EC 3, 1.1.3] activities tended to be higher than those of control group. Lipoprotein lipase (LPL) [EC 3.1.1.34] activity in adipose tissue was higher in the capsaicin and capsinoid-II groups than in the control group. These results showed that capsinoid can improve serum and liver lipid metabolism comparable to synthetic capsaicin.