<;P>;PROBLEM TO BE SOLVED: To provide a neurite extension promoting agent capable of promoting the regeneration of the central nerve. <;P>;SOLUTION: The neurite extension promoting agent contains, as an active component, a polypeptide having neurite extension promoting activity such as a polypeptide at least containing CEP-68 protein or its center region. A polypeptide having a neurite extension promoting activity was first found by the invention. The polypeptide has the activity to promote the extension of the neurite of the central nerve. Accordingly, the neurite extension promoting agent is useful for the regeneration of the central nerve. <;P>;COPYRIGHT: (C)2008,JPO&INPIT