Naphthalenedicarboxylic acid containing raw material and a mixture of the amine to obtain crystals of naphthalenedicarboxylic acid amine salt step in a mixture of water and an organic solvent; and purifying naphthalenedicarboxylic from crystals of naphthalenedicarboxylic acid amine salt obtained in the above step comprising the step of obtaining the acid, a method for producing a purified naphthalenedicarboxylic acid, (1) water, with the addition of an amine to a slurry containing an organic solvent and naphthalene dicarboxylic acid in the process of forming the naphthalene dicarboxylic acid amine salts, amine addition rate of per minute from 0.002 to 0.4 mol of naphthalene dicarboxylic acid 1 mol, or (2) a naphthalene dicarboxylic acid amine salt to an aqueous solution prepared by dissolving in water or an aqueous solution thereof solid a liquid obtained by liquid separation, the addition of amine to precipitate by insolubilize the metal content, precipitated are removed by solid-liquid separation of the metal component that is, to provide a method of manufacturing a purified naphthalenedicarboxylic acid.