New polyphosphazene containing oligooxyethylene side chains have been synthesized The polymer, PP, is readily soluble in all organic solvents including hydrocarbons but not in water. It readily forms polymer-metal salt complexes with alkali metal salts. Detailed de conductivity measurements by the complex impedance method have been carried out on the metal salt complexes of the polymer PP. The maximum conductivity observed for PP-LiBF4 (O:Li ratio, 8:1) complex is 5 x 10(-6) S-cm(-1) at 333 K.