The molecule of the title pyrazole derivative, C18H19BrN4S, is twisted. The central pyrazole ring, which adopts a flattened envelope conformation, is almost coplanar with the 4-bromophenyl ring, whereas it is inclined to the 4-(dimethylamino)phenyl ring making dihedral angles of 1.68 (6) and 85.12 (6)°, respectively. The dihedral angle between the two benzene rings is 86.56 (6)°. The dimethylamino group is slightly twisted from the attached benzene ring [C—C—N—C torsion angles = 8.4 (2) and 8.9 (2)°]. In the crystal, molecules are linked by intermolecular N—HS hydrogen bonds into chains along . The crystal is further stabilized by C—Hπ interactions.