The invention discloses a preparing method for composite peanut milk. The milk includes the following medical and edible dual purpose Chinese herb extracts: degreased peanut protein powder, fresh milk, whey protein, xylitol, soybean oligosaccharides, sterculia lychnophora, mulberries, longan, donkey-hide gelatin, lily, radix polygonati officinalis and the like, as well as blueberry pectin, modified soya bean lecithin, xanthan gum and calcium stearoyl lactylate. According to the composite peanut milk, the degreased peanut is adopted to reduce the content of fat, xylitol substitutes saccharose to reduce the content of sugar, the added whey protein and dietary fiber soybean oligosaccharides supplemented with medical and edible dual purpose Chinese herb extracts are adopted, so that the composite peanut milk is mild and nourishing; the added blueberry pectin is used for emulsifying other components and improves the mouthfeel, so that the composite peanut milk meets the requirements for the characteristics of high protein, low fat, less sugar and balanced nutrition in today's diet, is low in preparation cost, simple to operate, suitable for large-scale commercial process and excellent in social benefit and economic benefit.