In the title compound, C(10)H(12)N(2)O(3)·H(2)O, the Schiff base mol-ecule is approximately planar [within 0.189 (1) Å]. The inter-planar angle between the benzene and acetohydrazide planes is 8.50 (10)°. In the crystal, mol-ecules are linked into a three-dimensional network by strong and weak O-H⋯O and strong N-H⋯O hydrogen bonds. The hydr-oxy H atom deviates from the 4-hydr-oxy-3-methoxy-phenyl mean plane by 0.319 (2) Å, probably due to the involvement of this H atom in the O-H⋯O hydrogen bond. The weak O-H⋯O hydrogen bond is involved in a bifurcated hydrogen bond with R(1) (2)(4) motif. A weak C-H⋯π inter-action is also present.