Abstract: A method for preparing Cordyceps militaris nano-composite powder with protein-polysaccharide complex coacervation stability. The method includes sorting, drying, crushing suspending Cordyceps militaris ultrafine powder, emulsifying primarily, re-emulsifying, adjusting pH value and conducting spray drying. The emulsion stability after primary emulsification is not high, so re-emulsification technology is increased, and lactalbumin with higher emulsifying property and higher nutritional value are adopted as enhanced emulsifier, thus enhancing stability of an emulsifying system. The network envelopment stability of polysaccharide colloidal xanthan gum or kudzu powder is used to consolidate the stability of the emulsifying system, and a Pickering emulsifying system with multilayer of solid particle stability is constructed.