A La0.7Sr0.3Ga0.6Fe0.4O3-delta membrane with perovskite structure is fabricated by a conventional solid-state reaction. As the oxygen permeation flux of the La0.6Sr0.4Ga0.6Fe0.4O3-delta membrane was lower than commercial gas separation membranes, we coated a La0.6Sr0.4CoO3-delta layer to enhance the oxygen permeation flux. The La0.6Sr0.4CoO3-delta coating was very effective for increasing oxygen flux, as the flux was as much as 2 to 6 times higher than that of an uncoated La0.7Sr0.3Ga0.6Fe0.4O3-delta membrane. Moreover, the oxygen permeation flux was strongly influenced by the porosity of the coating layer. XRD analysis after the oxygen permeation confirmed that Ga-based membranes have a phase stability.