β-lactoglobulin (β-LG) is an important natural active nutrient and one of the main allergens in bovine milk. β-lactoglobulin is about 50% of the total whey protein， is the major whey protein in bovine milk， has strong heat sensitivity and allergenicity， and plays a key role in the high-quality dairy industry， not only as an evaluation index of heat treatment intensity of milk， but also as the marker protein of milk allergens in food. Therefore， it is very important to effectively identify and detect bovine β-lactoglobulin. Thirteen variants of bovine β-lactoglobulin have been reported， of which A and B are the common variants whose content are the highest. According to different detection principles， the article briefly describes three kinds of detection methods of milk β-lactoglobulin variants in recent years， and summarizes the principles， advantages， disadvantages and some application examples of electrophoresis， chromatography and immunoassay. The two quantitative methods of liquid chromatography and capillary electrophoresis were introduced emphatically， and the future development direction of bovine β-lactoglobulin was prospected.