Hot water soluble extract was prepared from Hericium erinaceus and its neuritogenic activity on PC12h cells was analyzed, which is a clone originating from a rat pheochromocytomon. The moisture content of freeze dried hot water extract was 12.08%. The extract was mainly composed of carbohydrate (51.24%) followed by crude protein (24.04%), crude fat (0.26%), dietary fiber (5.09), and ash (12.18%). Fatty acids, glucan and inorganic constituents were found as minor components. The neuritogenic activity of hot water extract was evaluated under microscopic observation of neurite outgrowth in PC12h cells and by measuring the neurite length of induvidual cell. The extract exhibited strong effect of neurite outgrowth in a dose-dependent manner from 0.01 mg/mL to 1 mg/mL, in which longer neurite outgrowth was observed as the treatment dose increased.