Provided is an efficient method of inducing differentiation of a pulp cell into an odontoblast. Also provided is an agent for inducing differentiation capable of inducing differentiation into an odontoblast efficiently. The method of inducing differentiation of a pulp cell into an odontoblast includes using a substance capable of activating a Wnt signaling pathway. Further, the agent for inducing differentiation includes a substance capable of activating a Wnt signaling pathway. Specifically, the substance capable of activating a Wnt signaling pathway is any one selected from sodium perchlorate, sodium perchlorate, lithium chloride, Norrin, and R-Spondin2.
