In the title compound, [Zn(C(14)H(13)N(4)O(2))(2)]·H(2)O, the Zn(II) centre is six-coordinated by four N and two O donors of two 2-acetyl-3-methyl-pyrazine (2-hydroxy-benzo-yl)hydrazonate ligands, and forms a distorted octa-hedral structure.