Anthracene-1,8-dicarboxylic acid, C16H10O4, crystallized in the noncentrosymmetric space group P2(1)2(1)2(1). The carboxyl H and O atoms are ordered. The carboxyl groups make angles of 13.9 (2) and 21.6 (2) degrees with the best-fit core plane and the average distance of the core atoms from this plane is 0.018 (12) A. The anthracene core displays near twofold symmetry. Each molecule is involved in cyclic-dimer hydrogen bonding with two other molecules so as to form zigzag chains of hydrogen-bonded molecules which are not cross-linked with one another. These discrete chains are separated from each other by C...C, C...H and H...H closest approaches.