Heteroprotein complex coacervation is a phase separation phenomenon that occurs between two oppositely charged proteins， and it has attracted increasing attention from food researchers. This review first introduced the definition and characteristics of the heteroprotein complex coacervation. Then， the typical systems of heteroprotein complex coacervation and the influences of the environmental factors on the coacervation process were summarized. Also， the applications of heteroprotein complex coacervation in the delivery of small molecule bioactives， the probiotic encapsulation， the separation and purification of proteins and the stabilization of emulsions were introduced in detail. Finally， the research direction of heteroprotein complex coacervation was prospected.