In the title compound, [HgCl(2)(C(12)H(19)N(3))], the Hg(II) ion is coordinated by three N atoms of the (1R,2R)-N-(pyridin-2-ylmeth-yl)cyclo-hexane-1,2-diamine ligand and by a Cl atom in the basal plane, and by a second Cl atom in the apical position, within a distorted square-pyramidal geometry. The coordination of the enanti-opure ligand to the metal atom renders the central N atom chiral with an S configuration, so the complex is enanti-omerically pure and corresponds to the S,R,R diastereoisomer. Mol-ecules are linked via weak N-H⋯Cl hydrogen bonds into a one-dimensional hydrogen-bonding supramolecular chain along the crystallographic b axis.