Two stable Ru(II) bipyridyl complexes were synthesized with the deprotonated forms of the azo ligands of 8-hydroxyquinoline (hq) as analogues and they were chromatographically separated. The extended azo ligands coordinated as a bidentate ligand and chelates to ruthenium(II) through 8-quinolinolate moiety,leaving the azo part free from coordination. The general formula of the complexes are [Ru(bpy)₂(q)]⁺. Here, q- is the deprotonated form of 5-phenylazo-8-hydroxyquinoline (Hq¹) and 5-(2-naphthylazo)-8-hydroxyquinoline(Hq²). The complexes were verified by ¹H NMR, ESI-mass, absorption-emission spectra, cyclic voltammetry and single-crystal X-ray structure determination. UV light-induced trans͢ cis isomerization and reverse isomerism i.e. cis ͢ trans around -N=N- bond at room temperature were proposed from the UVVisspectral changes as well as the changing of the colour of the solution of the complexes. In aid of understanding the electronic charge distribution and charge-transfer properties, computational studies employing DFT and TDDFT method have been executed