Background: Hair follicle is a self-renewing organ showing cyclicity, indicating the presence of hair follicle stem cells (HFSCs). Crif1 is a mitochondrial protein which regulates the synthesis and insertion of oxidative phosphorylation polypeptides by interacting with mitoribosomal large subunit. Previous study indicates that hair morphogenesis is severely hampered in epidermal specific Crif1 knockout newborn mice (K14-Cre;Crif1fl/fl). Objectives: We investigated the effect of hair follicle stem cell-specific mitochondrial dysfunction on the hair growth cycle. Methods: We generated HFSCs inducible conditional knockout mice for Crif1 gene. Results: K15-CrePR;Crif1fl/fl showed a retarded hair growth cycle. Furthermore, during transition between telogen and anagen, the activation of HFSCs was significantly reduced in K15-CrePR;Crif1fl/fl mice. However, FACS analysis showed that the considerable amount of HFSCs were present in hair bulge region of K15-CrePR;Crif1fl/fl mice. Conclusion: These results demonstrate that mitochondrial function in HFSCs is essential for the proceeding of hair growth cycle in terms of HFSC activation, but not for maintenance of HFSCs.