In the title hydrate, C(17)H(14)ClN(3)O·H(2)O, the dihedral angle between the quinoline fused-ring system and the benzene ring is 13.4 (2)° and the conformation about the C=N bond is E. In the crystal, N(h)-H⋯O(w) and O(w)-H⋯N(q) (h = hydro-zone, w = water and q = quinoline) hydrogen bonds generate a two-dimenstional network in the ac plane. A weak C-H⋯O inter-action helps to consolidate the packing.