To obtain proton-conducting organic materials with high conductivity under nonaqueous conditions, high thermal stability, and high resistance to acid, we prepared perfluorooctane-sulfonic acid (FOSA)/ poly(propylene carbonate) (PPC) composites with different weight ratios. The composite with the weight ratios of 3 shows a high proton-conductivity of 1.9 x 10(-5) S.cm(-1) at 30 degrees C under nonaqueous conditions.