The invention relates to milk powder for middle-aged and old people and a preparation method thereof. The formula of the product comprises 400-600 parts of fresh milk, 20-40 parts of desalted whey powder, 4-10 parts of concentrated whey protein powder, 6-7 parts of magnesium stearate, 2-8 parts of fructo-oligosaccharide, 0.2-0.6 part of docosahexaenoic acid, 0.4-0.8 part of eicosatetraenoic acid,1-5 parts of compound fruit and vegetable powder, 0.06-0.1 part of choline, 0.03-0.05 part of taurine, 0.1-0.5 part of compound vitamins and 0.2-0.5 part of compound trace elements. The product is rich in nutrition and balanced and reasonable in proportion of various nutrients, has good taste and mouth feel, has no bitter taste of traditional Chinese medicines, has no peculiar smell, and can be easily accepted; and furthermore, because of the presence of the magnesium stearate, the magnesium stearate can effectively promote the absorption of the human body to nutrient substances so as to enhance the immunity of the human body.