Interests on gas separation using carbon membranes have increased due to good thermal and chemical stabilities. In this study, the carbon membranes derived the thermally stable and labile polymer blends were prepared using polymer blends of poly(2,6-dimethyl-1,4-phenylene oxide)(PPO)/Polypyrrolidone (PVP). The characterization of the pore structure for the carbon membranes confirmed that the addition of the thermally labile polymer decreased the pore characteristic values. The permeation results for the PPO/PVP derived carbon membranes showed a strong dependency upon the pyrolysis temperature. The permeation results showed that the introduction of the thermally labile polymer lead to control the pore structure.