Well-defined cyclic-polymers (cyclic-PAzoMMAs), bearing side-chain phenylazo naphthalene chromophore, were successfully synthesized by the combination of atom transfer radical polymerization (ATRP) and copper(I)-catalyzed azide/alkyne cycloaddition click reaction, as verified by GPC, H-1 NMR, FTIR, and MALDI-TOF mass spectrometry. The cyclic-PAzoMMA showed higher glass transition temperatures than the linear-PAzoMMA with the same molecular weight. Interestingly, the cyclic-PAzoMMA exhibited deeper modulation depth (M.D.) induced by SRG, larger value of the photoinduced birefringence, increased fluorescence emission, and longer fluorescence lifetime in comparison with its linear counterpart.