In the title complex, [HgI(2)(C(12)H(12)N(2))], the Hg(II) atom has a distorted tetra-hedral coordination formed by two N atoms of the 6,6'-dimethyl-2,2'-bipyridine ligand and two terminal I atoms [N-Hg-N = 70.1 (2) and I-Hg-I = 130.59 (3)°]. The crystal packing features π-π contacts between the pyridine rings of adjacent mol-ecules [centroid-centroid distance = 3.773 (5) Å] and also between a pyridine ring of one mol-ecule and the five-membered chelate ring of an adjacent mol-ecule [centroid-centroid distance = 3.668 (4) Å].