Effect of polar acrylamide (AM) group on the conductivity of Li+-conducting polymers is studied，in which the conductivity data are analyzed by Vogel-Tammann-Fulcher(VTF)equa-tion and interpreted by the configurational entropy model．The linear VTF pohs revealthat there is a close correlation between ionic conductivity and segmental motion of the polymers．Polar AM groups may enhance the dissociation degree of the salt species and lower the activa-tion energy of exchange process of the Li+-O bonds during ionic transport，but also increase the rigidity of polymer segments．As a result，ionic conductivity of the copolymers is promot-ed as long as AM content is below ca．15 wt％．