The title compound, C(18)H(17)N(3)S(2), was synthesized by the reaction of 5-(3,5-dimethyl-phen-yl)-1,3,4-thia-diazol-2-amine and 4-(methyl-sulfan-yl)benzaldehyde. An intra-molecular C-H⋯S hydrogen bond results in the formation of a planar (r.m.s. deviation = 0.003 Å) five-membered ring. In the crystal structure, inter-molecular C-H⋯N hydrogen bonds link the mol-ecules to form layers parallel to (011).