Abstract: Yeast protein, due to its rich nutrition, low-fat, and environment-friendly production process, is a novel food ingredient for alternative protein and has received widespread attention in the food industry in recent years. This paper reviews recent advances in yeast protein's functional properties, the impact of modification technology on its functional properties, and its applications in food. Regarding functional properties, this paper systematically elaborates on yeast protein's solubility, foaming capacity, emulsifying capacity, water-holding capacity, and oil-holding capacity, and clarifies the role of each functional property in food processing. Regarding modification technology, various methods, including physical, chemical, and biological modification, are discussed, analyzing the impact of different technologies on yeast protein's functional properties. Regarding food applications, this paper focus is on evaluating yeast protein's role in food ingredient substitution, the enhancement of nutritional quality, and the improvement of processing characteristics. In addition, this paper analyzes the key challenges of yeast protein, and provides an outlook on its future development, aiming to provide a reference for the further development and utilization of yeast protein.