By a method of laser firing, a high zirconia containing (70%) composite membrane on porous ceramic tubing was successfully fabricated. The laser sintered composite membrane was characterized by gas separation/permeation experiments. In the separation experiment of a CO2-CH4 gaseous mixture, it was found that the separation factor of CH4 over CO2 was 1.15. In the pure gases permeation experiment, it was found that Knudsen diffusion is considered to be predominant in the permeation mechanism for pure gases H-2, He, CH4, N-2, O-2, and CO2, and the permeation mechanism of H2O at lower temperature depends mainly on surface diffusion and on Knudsen diffusion at higher temperature.