An objective of the present invention is to provide a new substance having a cerebral nerve cell neogenesis effect. Another objective is to provide a cerebral nerve cell neogenesis agent that is effective in treating and/or preventing neurological disorders utilizing the substance. With the present invention, a cerebral nerve cell neogenesis agent containing a plasmalogen as an active ingredient is provided. In particular, a preferable cerebral nerve cell neogenesis agent contains, as an active ingredient, a biological tissue (preferably, an avian tissue) extracted plasmalogen mainly including an ethanolamine plasmalogen and a choline plasmalogen.
