Intractable neuronal diseases are treated by inducing differentiation of neural stem cells into neurons without accompanying a risk such as cytotoxicity and infection. Intractable neuronal diseases, such as Parkinson's disease, cerebral infarction, Alzheimer's disease, spinal cord injury, brain contusion, amyotropic lateral sclerosis, Huntington's disease, malignant tumor, and the like, are treated by regeneration therapy by transferring VHL peptides which can induce differentiation of neural stem cell into neurons into neural stem cells to induce differentiation of neural stem cells into neurons or by administering VHL peptides directly into a human body to induce differentiation of endogeneous stem cells into neurons.