Crystal structure of 2,4,5-trimethylbenzoic acid (2,4,5-TMBA) has been determined by X-ray studies. Two molecules of 2,4,5-TMBA on association affords centrosymmetric carboxyl dimers. 2,4,5-TMBA can be synthesized from pseudocumene. Vibrational analysis of monomeric and dimeric foms of 2,4,5-TMBA have been reported.