The present invention relates to an oral solution preparation containing memantine. It is characterized by that said preparation includes pH regulating agent, bacteriostatic and corrective. The pH regulating agent is one or several kinds selected from citric acid, tartaric acid, fumaric acid, malic acid and maleic acid, the bactriostatic is selected from benzoic acid and its salt or egtazic acid and its salt, and the corrective is one or several kinds selected from cane extract (trichlorocane), stervioside and saccharine sodium. |