Two kinds of amino‐functionized, triphenylamine and fluorene based copolymers, PFT‐N and PTFF‐N, were synthesized by palladium‐catalyzed Suzuki coupling reaction. The corresponding quaternized polyelectrolytes PFT‐NBr and PTFF‐NBr were obtained through post‐polymerization. The quenching behaviors of PFT‐NBr and PTFF‐NBr in methanol were investigated by the titration of Fe(CN). All of these polymers were investigated as emitting layer in multilayer PLEDs. Devices' performance together with electrochemical properties of these polymers indicate that both of the hole and the electron injection capabilities of them were improved due to the simultaneous introduction of the triphenylamine segment and the aminoalkyl (ammonium) group.magnified image