The aims of this investigation was to examine the anti-obesity effects of oral administration with Mulberry leaves extraction in the high-fat diet induced obesity rats. We investigated the anti-obesity effects of the extract from Mulberry leaves on the progress of high fat diet for 8 weeks. Experimental rats were divided into 5 different experimental groups including an normal group (normal dieat; n=10), control group (high fat diet; n=10), I (Mulberry leaves extraction 100 mg/kg oral administration induced obesity; n=10), II (Mulberry leaves extraction 300 mg/kg oral administration; n=10), and III (Mulberry leaves extraction 500 mg/kg oral administration; n=10). It is to analysis changes in body weight, epididymal fat weight, blood lipid profiles, and fat histological findings. Body weights were significantly increase in control group than normal groups(p<0.05). The level of total cholesterol, LDL-C and TG were significantly lower in experimental groups than control group (p<0.05). In histopathologic finding of fat-tissue around testicle experimental group I and II were more decreased than high fat diet-induced control group in fat cell size. These results suggested that the Mulberry leaves extraction oral administration made the increase of anti-obesity effect in high-fat diet induced obesity rats.