IN THE CRYSTAL STRUCTURE OF THE TITLE COMPOUND [SYSTEMATIC NAME: 2-hy-droxy-2-(4-hy-droxy-benz-yl)butane-dioic acid methanol monosolvate], C(11)H(12)O(6)·CH(3)OH, the dihedral angles between the planes of the carboxyl groups and the benzene ring are 51.23 (9) and 87.97 (9)°. Inter-molecular O-H⋯O hydrogen-bonding inter-actions involving the hy-droxy and carb-oxy-lic acid groups and the methanol solvent mol-ecule give a three-dimensional structure.