Obesity is one of the most common disorders encountered in clinical practice. It is a major risk factor for many chronic diseases. Green tea is reported to contain thousands of bioactive ingredients which are almost contributed by polyphenols which play a key role in prevention and treatment of many diseases including obesity. Our investigation aimed to study the effect of oral administration of aqueous extracts of green tea on obesity by using experimental rats. Thirty adult male albino rats (160-200gm) were divided into five experimental groups: The first considered as control group and fed on normal diet, while other four groups fed on high fat diet for three weeks to induce obesity. Obese rats were divided into three equal groups (n= 4 rats). Second group contain obese rats. Third, fourth and five group fed on 10% and 20% of green tea extract respectively. At the end the experimental period (28 days), the body weight gain, food intake, feed efficiency ratio, blood sugar, liver enzymes (ALT, AST, ALP), and lipid profile were evaluated. Our results revealed that the consumption of green tea extract produced a significant reduction in body weight in obese rats and enhances liver functions.