The purpose of this study was to investigate the dietary effects of a mixture of herbal extracts administered for four weeks to an experimentally induced obese rats fed a high-fat diet. In male Sprague-Dawley rats (100±10 g) were fed high fat diets for six week. The groups were divide equally into five groups. The normal group was a normal diet group (ND), the obesity control group was a high fat diet group (HFD), the experimental groups consisted of a high fat diet and a combined plant extract of either 100, 300, or 500 mg/kg. The body weight and visceral fat of the HFD group were heavier than those of ND group, whereas those of groups administered combined plant extracts gradually decreased after four weeks. The levels of serum triglyceride, AST, and ALT were significantly reduced in the combined plant extract administered groups compared with the HFD group. There were no differences in the levels of serum total cholesterol and HDL-cholesterol between experimental groups. Theses results suggest that combined plant extracts may inhibit obesity in rats fed HFD and histologic findings at liver, adipose cells significantly decreased in the combined plant extracts administered groups compared with HFD groups. According to the results of this study, the conclusion was that combined plant extracts administration can be an effective method for diet effects on obesity induced rats and possible application for obese persons.