Objective : To compare the osteogenic differentiation ability of human apical papilla stem cells (SCAPs) , dental pulp mesenchymal stem cells (DPSCs) and alveolar bone mesenchymal stem cells (ABMMSCs) in vitro. Methods : The apical papilla stem cells , dental pulp mesenchymal stem cells and alveolar bone mesenchy⁃ mal stem cells isolated from the third molars and alveolar bone tissues were cultured and passaged. The morphology of primary and P3 generation cells was observed under a microscope. Flow cytometry was used to detect cell immunophenotype. Real⁃time fluorescent quantitative PCR (qRT⁃PCR) and cell counting kit⁃8 were used to analyze cell senescence and proliferation ability. After osteogenic induction , alkaline phosphatase (ALP) and alizarin red staining and qRT⁃PCR were used to detect osteogenic related genes to compare osteogenic ability. Results: There was no significant difference in the morphology of the three cells , which showed the morphology of fibroblasts , long spindle⁃shaped , smooth and uniform after passage. There were no senescence differences among the 3 types of cells , all of which maintained stable proliferative capacity ; the proliferation capacity of SCAPs was significantly higher than that of the other 2 types of cells , and the proliferation capacity of ABMMSCs was weaker; ALP staining and alizarin red staining after 7 and 14 d osteogenesis induction showed that the osteogenic ability of ABMMSCs was significantly stronger than that of SCAPs and DPSCs ; qRT⁃PCR showed that ABMMSCs had the most significant inrease in osteogenesis⁃related genes. Conclusion SCAPs , DPSCs and ABMMSCs have stable biological properti and can undergo osteogenic differentiation , and ABMMSCs have stronger osteogenic ability than DPSCs and SCAPs in vitro.