A pair of enantiomerically pure cobalt phosphonates were reported, namely, R(S)-Co3(2-ppap)2(1,3′-dpp)2(H2O)2·2H2O (R-1 or S-1), where 2-ppapH3 is 3-phenyl-2-［(phosphonomethyl)amino］propanoic acid, and 1,3′-dpp is 1,3-di(4-pyridyl)propane. It shows layer structures, where the {Co1O4N2} octahedral, {Co2O3N2}, and {Co3O3N2} trigonal-bipyramidal are each involved in corner sharing with {PO3C} tetrahedra with formation of inorganic metal chains containing 8-member rings. The inorganic metal chains are crossed-linked through 1,3′-dpp, forming a supramolecular layer in the ac plane. The thermal analysis, and optically active properties of compounds R-1 and S-1 were investigated.