The aim of the study was to investigate the preventive effects of dietary Garcinia cambogia extract on lipid metabolism and serum activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyle transferase (GGT) in rats fed high-lipid diet. Thirty female, one-year-old Sprague-Dawley rats were used and separated into three equal groups. Group 1 (control group) was fed basal diet (2% liquid vegetable oil, 0% cholesterol), while the diets of both group 2 and 3 contained vegetable oil (2% liquid and 5% hydrogenated vegetable oil) and cholesterol (3%). 4.5% (w/w) Garcinia cambogia extract was added to the diet of group 3 from day 45. Blood samples were withdrawn from all rats on days 0, 45 and 75. Serum levels of total protein, LDL-cholesterol and phospholipid were lower in the control group than in the other two groups, and there were no significant differences between these two experimental groups at the end of the study (P<0.05). Serum triglyceride concentrations rose significantly in the Garcinia cambogia-supplemented group (group 3). HDL-cholesterol levels were significantly different between the three groups (P<0.05). The highest levels were in the control group. Serum ALT activities were not significantly different between the groups at the end of the study. Serum AST and GGT activities were significantly lower in the groups 2 and 3 than those in the controls, respectively. Fat feeding caused rising lipid indices in serum, while Garcinia cambogia supplementation to the fatty diet failed to decrease the rise in serum lipid indices in the present dose. The higher doses of Garcinia cambogia extract should be investigated.