Disclosed is a method for the production of a diet food with medicinal herbs. According to the method, herbs which have physiological activities suitable for dieting are selected by making reference to various reports and through experimentation. Depending on nutritional and pharmaceutical ingredients responsible for the physiological functions and activities, the herbs are classified into three groups, and combined with each other to form a composition which is extracted in such a manner that as few effective ingredients are lost as possible. The diet food is effective for the prevention and treatment of obesity.