Abstract: Objective： To evaluate the effect of TNF-α on the autophagy level in periodontal ligament stem cells (PDLSCs) and jaw bone marrow mesenchymal stem cell (JBMMSCs). Methods：The human PDLSCs/JBMMSCs were isolated and cultured by the method of trypsmization, the flow cytometry and real-time quantitative PCR screened the concentration of TNF-α (The maximum concentration that didn’t cause the apoptosis of cells in a short period). Western blot was applied to estimate the level of autophagy and apoptosis at different time points after PDLSCs/JBMMSCs co-culturing with TNF-α. Results： We have successfully screened the concentration of TNF-α. When co-culturing with TNF-α, activated autophagy reduced apoptosis of PDLSCs/JBMMSCs in short time, and vice versa in long time. Conclusions： The inflammatory cytokines TNF-α could activate the autophagy level, and avoid apoptosis of PDLSCs/JBMMSCs under certain conditions.