A solid state facilitated transport separation membrane prepared by forming a polymer electrolyte layer consisting of a polymer and a metal salt to a porous membrane having good permeance and mechanical strength; the polymer electrolyte facilitated transport separation membrane thus prepared is characterized in that the permeance and selectivity to alkene hydrocarbons is high, and that the complex is formed by a polymer ligand and a metal in the polymer electrolyte maintains its activity as a carrier of alkene even under dry operation.