We report the synthesis, characterization, and photophysical and photochemical properties of [Ru(bpy)2(py)2]2+@Zn-oxalate metal-organic framework (Ru@MOF; bpy is 2,2'-bipyridine and py is pyridine). In Ru@MOF, the cavities of the anionic Zn-oxalate MOF tightly encapsulate [Ru(bpy)2(py)2]2+ complexes, thereby altering the vibrational and electronic states of [Ru(bpy)2(py)2]2+ and preventing photosubstitution of py ligands. [Ru(bpy)2(py)2]2+ in Ru@MOF exhibits significantly increased photoluminescence lifetime and quantum yield, likely through destabilizing the dd state and enhancing photochemical stability.