Objective: The study of the functional properties of active substances in postbiotic products is key to elucidating their probiotic mechanisms. By investigating the metabolic components and bioactive functions of Bifidobacterium cells， the probiotic functions of Bifidobacterium as a postbiotic can be better characterized. Methods: The dried cells of Bifidobacterium adolescentis B8589 and Bifidobacterium bifidum B1628 obtained from high-density fermentation were selected as the research subjects. Untargeted metabolomics was used to study the functional components of the cells. Results: A total of 48 bioactive metabolites， primarily flavonoids， lipids， and lipid-like molecules， were identified in B. adolescentis B8589， including daidzein and galangin. Meanwhile， 35 bioactive metabolites， primarily organic heterocyclic compounds， lipids， and lipid-like molecules， were identified in B. bifidum B1628， including tetrahydropyrimidine and isoglycyrrhizin. Among these， both B8589 and B1628 shared active metabolites mainly composed of flavonoids. These bioactive components exhibit antioxidant， antitumor， and anticancer properties， contributing positively to human health. Conclusion: During the development of Bifidobacterium-based postbiotic products， the identification of beneficial active components within Bifidobacterium cells can serve as a valuable reference for evaluating functional components and facilitating industrial applications.