Abstract: Poly(aryleneethynylene) derivatives containing 1,2,3benzotriazole group and bearing side chains with different lengths were synthesized by Pd(Ⅱ) complex catalyzed Sonogashira reaction with 4,7dibromo2-dodecylbenzotriazole and 2,5diethynyl1,4-dioxybenzene. The chemical structure of these polymers were characterized by 1H-NMR and FT-IR. Results show that the number average molecular weight of these polymers range from 0.93×104 to 1.13×104 . These new polymers can be solved easily in common organic solvents such as CHCl3 and THF. The film of these polymers can be prepeared easily due to the long alkyl chain on benzotriazole and the long alkoxyl chain on benzene ring. The maximum absorbance of these polymers in cast film appeared at 490 nm, which has redshifted 45 nm from that in CHCl3 solution. The emission peaks of these polymers in cast film has redshifted from that in CHCl3 solution.