The invention discloses a nutritionally balanced food composition for weight loss, which comprises the following components: oat, yam, lotus root, yellow corn, potato, millet, black rice, job's tears, pumpkin, konjac, black sesame, red bean and black bean , mushrooms, walnuts, wolfberry, red dates, kudzu root powder, hawthorn powder, whey protein concentrate, soybean protein isolate, deep-sea fish collagen, olive oil, perilla seed oil, maltodextrin, L-carnitine, milk calcium; The invention also discloses a preparation method of a nutritionally balanced food composition for weight loss. Regular consumption of these food compositions can effectively reduce weight, and has the functions of protecting liver and kidney, protecting cardiovascular and cerebrovascular, regulating spleen and stomach, beauty and fitness. and other functions.