The title compound, C(8)H(10)O(4), was isolated from culture extracts of the endophytic fungus Xylaria sp. (PB-30). The cyclo-hexenone ring exhibits a flattened boat conformation. In the crystal structure, mol-ecules related by translation along the b axis are linked into chains through O-H⋯O hydrogen bonds. Weak non-classical C-H⋯O contacts are also observed in the structure.