In the title compound, C(14)H(12)ClN(3)OS, the short exocyclic N-C bond lengths indicate resonance in the thiourea part of the mol-ecule. The title compound is stabilized by an intra-molecular N-H⋯N hydrogen bond, which results in the formation of a six-membered ring. In addition, it shows a synperiplanar conformation between the thio-carbonyl group and the pyridine group. Inter-molecular N-H⋯S and C-H⋯O inter-actions are also present.