In the title compound, C16H13ClN2S, the pyrazole ring is almost planar with an r.m.s. deviation of 0.0457 Å which forms dihedral angles of 2.875 (4) and 84.83 (7)° with the chloro-substituted benzene ring and the methylsulfanyl-substituted ring, respectively. In the crystal, N—H...N and C—H...Cl hydrogen bonds contribute to the formation of a three-dimensional network. In addition, several offset π–π stacking interactions are also present.