2,5-Dihydroxy-1,4-benzoquinone or 2,5-dihydroxy-para-benzoquinone is an organic compound with formula C6H4O4, formally derived from 1,4-benzoquinone by replacing two hydrogen atoms with hydroxyl (OH) groups.

It is a yellow solid[1] with planar molecules[2] that exhibits ferroelectric properties.

[3] The compound is a weak acid: one or both hydroxyls can lose a proton to yield the anions C6H3O−4 (pKa1 = 2.95) and C6H2O2−4 (pKa2 = 4.87), respectively.

The latter forms a variety of metal complexes, functioning as a binucleating ligand.

[4] The compound has been identified as partly responsible for the color of aged cellulosic materials.