Metal-containing polymers, PPO–DPP–Pd, PPO–CPA–Pd, PSF–DPP–Pd, PSF–CPA–Pd (DPP = diphenylphosphinyl, CPA = o-carboxy phenyl amino), PPO–M (M = Pd, Cu, Co, Ni), and PSF-Pd, were prepared by incorporating metal chloride with either modified or unmodified poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) and polysulfone (PSF). The Pd-containing polymers exhibit catalytic activity in the hydrogenation of cyclopentadiene under mild conditions (40°C, 0.1 MPa) both in alcohol solution and in the gas phase. The selectivity in the hydrogenation of diene to monoene in the gas phase can be controlled by adjusting the hydrogen partial pressure. The metal-containing polymers, PPO–M and PSF–Pd, can be cast easily into the membranes. The H2/N2 permselectivity for PPO–M is higher than that for unmodified PPO, whereas the permeability of H2 changes slightly. The H2 permeability and H2/N2 permselectivity for the PPO–Pd membrane are up to 67.5 barrers and 135, respectively. © 1993 John Wiley & Sons, Inc.