In the asymmetric unit of the title compound, [HgCl2(C16H14N4S)], the HgII cation is linked to two Cl atoms and two imidazole N atoms of the chelating bis[(1H-benzimidazol-2-yl)methyl]sulfane ligand, forming a slightly distorted tetrahedral environment. The substitued imidazole rings of the ligand are almost perfectly planar [with maximum deviations of 0.017 (3) and 0.012 (3) Å] and form a dihedral angle of 42.51 (5)°. The crystal packing can be described as alternating layers parallel to (010). In this arrangement, N—H⋯Cl hydrogen bonds between the N—H groups of the benzimidazole moieties and chloride ligands are responsible for the formation of the chain-like packing pattern along [010] exhibiting a C(6) graph-set motif.