Milk protein is the main index to determine the nutritional quality of milk， while thermal processing will affect the stability of whey proteins， especially β-lactoglobulin. With the heat treatment temperature， whey protein denaturation， self-aggregation occurs. The dimeric structure of β-lactoglobulin expands and binds to α-lactalbumin. Negatively charged lactoferrin binds positively charged β-lactoglobulin， bovine serum albumin， and immunoglobulin G. In the meantime， β-lactoglobulin undergoes sulfhydryl-disulfide exchange with κ-casein and milk fat globule protein. In addition， whey protein and lactose glycosylation reaction. Whey protein and calcium through ionselectrostatic groups binding force. Whey protein through the disulfide bond with the milk fat aggregation reaction. All of the above reactions affect the thermal stability of the dairy product， ultimately affecting the quality of the product. In this paper， the thermal induced polymerization and its pathway of whey protein were investigated， and the process and mechanism of interaction between whey proteins and other milk components were clarified. It will contribute to control the interaction of milk composition system during processing， and has important theoretical significance to improve the thermal stability， gel， water holding capacity and other functional properties of dairy products. Broaden whey protein as an ingredient in the application of food systems.