Quantitative analysis of beef, chicken in beef products was achieved using species-specific peptides and liquid chromatography-tandem mass spectrometry (LC-MS/MS) in this study. Beef meat was mixed with pork and chicken at ratios of 10%, 50% and 80%, separately. Validation of the species-specific peptides and quantitative analysis of meat products prepared in our laboratory were conducted, showing linear correlation coefficients above 0.99. Meanwhile, 10 commercially available beef products were detected, and a quantitative analysis method based on species-specific peptides was established. The results showed that the developed method allowed quick and effective identification and quantitative analysis of beef products, providing new ideas for the authentication and quantitative analysis of processed meat products.