Abstract: Glycopeptides play important roles in many biological processes. However, the structural elucidation of glycoprotains(peptides) remains a major challenge due to the complexities of their structures. Tandem mass spectrometry provides a powerful method for determining peptides and oligosaccharide composition, as well as structural information of glycoproteins(peptides) with high sensitivity. Oligosaccharide structures differ from peptides because of a large number of linkage combinations and branching. This complexity makes the analysis of oligosaccharide unique from that of peptides. There are various methods of dissociation and fragmentation for different precursors. Depending on the magnitude of energy and ionized methods, the induced dissociation, electron driven dissociation and isomerization are used jointly and alternately as electron transfer high-energy collision dissociation (EThcD), electron transfer collision induced dissociation (ETciD), and energy step CID/HCD, etc. To obtain the structure information of oligosaccharides and peptides based on the ionized dissociated fragments, united analytical techniques and strategies with separation methods and database analysis have been applied. This review summarizes the methods currently used for fragmentation of tandem mass spectrometry, as well as the problem of spectral interpretation, and introduces some softwares for mass spectrometry analysis. With more and more in-depth research in the field of food, the analysis and structure-activity study of glycoprotein (peptide), which is an important bioactive and functional component, has become an important entry point for deepening processing technology and improving the added value of products and ensuring food safety. It is expected to use advanced analytical techniques of biology, chemistry and other disciplines to expand ideas and provide methods for the identification of important ingredients of food raw materials and the study of structure-activity relationship.