Abstract: Proteins play a critical role in the food industry due to their unique structural and functional properties. However, these properties can be altered by environmental factors during processing, leading to changes in their structure and function that limit their applications. Glycosylation modification is a spontaneous protein modification reaction widely used in the food industry. It offers advantages such as mild reaction conditions, stable modification products, and the absence of toxic or harmful byproducts. The glycosylation reaction combines the functional properties of proteins and sugars, significantly enhancing the functional attributes of proteins when the reaction is effectively controlled. This enhancement expands the potential applications of proteins in the food industry. Therefore, building upon a summary of the methods of the glycosylation reaction, this paper examines the changes in protein properties—specifically solubility, emulsification, gelation, foaming, and thermal stability—following glycosylation modification. Furthermore, it explores the potential applications of this modification in the food industry, aiming to provide valuable references for research on protein modification, particularly glycosylation, to enhance functionality and broaden usage.