MicroRNA (miRNA, miR) is essential in regulating cell differentiation either by inhibiting mRNA translation or by inducing its degradation. However, the role of miRNA in odontoblastic cell differentiation is still unclear. In this study, we examined the molecular mechanism of miR-27-mediated regulation of odontoblast differentiation in MDPC-23 mouse odontoblastic cells derived from mouse dental papilla cells. The results of the present study demonstrated that the miR-27 expression increases significantly during MDPC-23 odontoblastic cell differentiation. Furthermore, miR-27 up-regulation promotes the differentiation of MDPC-23 cells and accelerates mineralization without cell proliferation. The over-expression of miR-27 significantly increased the expression levels of Wnt1 mRNA and protein. In addition, the results of target gene prediction revealed that Wnt1 mRNA has an miR-27 binding site in its 3’UTR, and is increased by miR-27. These results suggested that miR-27 promotes MDPC-23 odontoblastic cell differentiation by targeting Wnt1 signaling. Therefore, miR-27 is a critical odontoblastic differentiation molecular target for the development of miRNA based therapeutic agents in dental medicine.