Abstract: Two polyamides(P1,P2) containing both azobenzene and 1,3,4-thiadiazole were synthesized.Their structures and properties are characterized by FT-IR,¹H NMR,GPC and TGA.The intrinsic viscosity of P1 and P2 are 0.14 dL/g and 0.12 dL/g,the M_w and polydispersity index(PDI) of P1 and P2 are 28.8,24.8 kg/mol and 1.71,1.74,respectively.Temperatures at mass loss of 5% for P1 and P2 are 320℃ and 322℃,respectively.The introduction of long side chain of alkoxy significantly improved the solubility of the two polymers in common organic solvents such as chloroform,tetrahydrofuran and so on.Their optical properties were investigated by UV-Vis absorption spectroscopy and fluorescence emission spectroscopy.The results indicated that the azobenzene in the polymers involved a trans-cis photoisomerization under the radiation of 365 nm UV light;the contents of cis-isomer-photostationary in P1 and P2 are 86.8% and 77.4% with corresponding efficiency of 82.7% and 73.7% for the anti-cis isomerization.Fluorescence emission peaks of P1 and P2 appeared at 418 nm and 428 nm under excitation at 366 nm and 363 nm.