Abstract: A process for producing a high-purity naphthalenedicarboxylic acid having an improved hue or an excellent hue from a crude naphthalenedicarboxylic acid obtained by the oxidation of dialkyl naphthalene, industrially advantageously at high yields, which comprises dissolving a crude naphthalenedicarboxylic acid obtained by the oxidation of dialkyl naphthalene in an aqueous solution containing an aliphatic amine, an alicyclic amine or acetonitrile, removing heavy metal components contained as impurities until the content of the heavy metal components based on the crude naphthalenedicarboxylic acid is 100 ppm or less, and heating the aqueous solution containing a naphthalenedicarboxylic acid amine salt to distill off the amine.