Gelatin is adulterated in various foods, which can be identified by mass spectrometry (MS) to detect characteristic peptides. The paper aims to review the application of MS in qualitative and quantitative analysis of gelatin. The identification results are affected by many factors, including the process of gelatin production and processing, the pre-treatment method and type of MS. At present, the traceability of gelatin mainly exists in pure gelatin, mixed gelatin and food systems. The quantification of gelatin is mainly through external reference and labeled internal standards. In the future, reducing the loss of gelatin during extraction, obtaining the maximum target characteristic peptide and improving the accuracy of MS should be focused on. In addition, the quantitative application of MS should be expanded to meet the market demand.