A novel polypyridyl ruthenium(II) complex with a six membered chelate ring ([Ru(dmb)(2)(8pyq)](2+)) was designed and synthesized. The oxidation potential was shifted to the negative potential direction, and relatively intense metal-to-ligand charge transfer absorption in the longer wavelength region was observed for [Ru(dmb)(2)(8pyq)](2+) compared with the reference complexes without any six-membered chelate rings. The electrochemical and spectroscopic properties of [Ru(dmb)(2)(8pyq)](2+) were discussed in terms of the chelate structure and coordination geometry with utilization of theoretical calculations.