The invention relates to diet food, in particular to pure natural weight-loss granules balancing nutrition in the body and a preparation method thereof. The weight-loss granules are prepared from dried sweet potatoes, semen sterculiae lychnophorae, chlorococcum, radix panacis quinquefolii, poria cocos, semen sesami nigrum and L-arabinose. The semen sterculiae lychnophorae, the radix panacis quinquefolii, the poria cocos, the chlorococcum and the L-arabinose are crushed by adopting a cell wall breaking process, so that the prepared product is easily and rapidly absorbed, the chlorococcum can replenish chlorophyll and protein, the L-arabinose can inhibit the absorption of saccharose, the radix panacis quinquefolii tonifies qi and nourishes yin to increase the physical strength during weightloss, the semen sterculiae lychnophorae improves peristalsis to expel toxins in the body, the semen sesami nigrum moistens the five internal organs, the poria cocos reduces the body temperature, the combination of the raw materials is the perfect diet food, and weight regain cannot occur after weight loss.