BACGROUND: Traditional medicine can be considered as a method to reduce dietary obesity. OBJECTIVS: The aim of the present study was to assess the protective effect of Iranian green and black tea on diet induced obesity. METHODS: Twenty four male Wistar rats (180±20 g) were divided into four groups. Control group was fed with rat regular diet (4% fat), and the three reminder groups were fed by high fat diet (25% fat). While control (C) and a high fat group (HF) had ad libitum access to water, the rest high fat groups had free access to drinking black tea (HF+BT) or green tea (HF+GT) instead of water. Eight week later rats were euthanized, weighed and their abdominal fat and organs separated and weighed. RESULTS: While Feed intake showed significant decrease in HF group compared with the control group (99.25±12.03 vs. 113.59±14.40 g/day; p<0.05), the levels of energy intake (454.54±55.09 vs. 405.52±51.43 kcal/day; p<0.05) and weight showed increase (283.33±13.84 vs. 223.33± 15.11g; p<0.05). Green and black tea made decrease in body weight gain compared to the HF group (71.67±1.61g and 57±12.95 vs. 104.33±21.75 g; p<0.05). However, the abdominal fat was just lower in HF+BT group than the HF group (2.90±0.56 vs. 4.19+.77g; p<0.05). CONCLUSIONS: Consumption of Iranian black and green tea may help to regulate body weight and reduce weight gain induced by high caloric food.