Abstract: A process for producing dimethyl 2,6-naphthalene-dicarboxylate by reacting 2,6-naphthalene-dicarboxylic acid with methanol which comprises effecting the reaction at 200.degree. to 350.degree. C. in the presence of trimethyl trimellitate as an essential solvent and optionally, at least one solvent selected from methyl benzoate, methyl toluate and dimethyl o-phthalate preferably by at least two-stage continuous reaction method. The above process is capable of enhancing the rate of esterification reaction and producing purified objective product in high yield for a long period of time in a stable operation without causing any operational trouble such as corrosion and clogging the production equipment.