In the title compound, C(14)H(13)N(3)S·H(2)O, the thio-semicarbazide group is nearly planar, with a maximum deviation of 0.072 (2) Å from the ideal least-squares plane, and shows an E conformation. In the crystal packing, the water mol-ecules are involved in an extensive inter-molecular N-H⋯O hydrogen-bond network, assisted by O-H⋯S inter-actions, which link the independent mol-ecules into chains extended along b axis. An intra-molecular hydrogen N-H⋯N bond helps to stabilize the mol-ecular conformation.