In the structure of the title compound, C(17)H(13)BrN(4)O(2)S, the dihedral angle between the two benzene rings is 38.5 (1)°; the angle between the 4-bromo-benzene and thia-diazole rings is 1.3 (1)°. The conformations of the N-H and C=O bonds are anti with respect to each other. The structure displays inter-molecular N-H⋯O and C-H⋯O hydrogen bonding, with both interactions leading to inversion dimers.