Abstract: A porous La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF6428) layer coated on the dense substrate, made from the same material has been prepared. The first part of the study focused on the development of dense LSCF6428 substrate with gas tight properties by controlling the sintering conditions. To further improve the performance of LSCF6428 perovskite membrane, an effort was made on surface modification by coating a porous LSCF6428 layer on dense membrane surface. The characterization of the thermal stability (TGA), phase structure (XRD), morphology (SEM) and oxygen desorption properties (O2-TPD) were investigated. The cross-sectional images of the surface modified membrane system indicated that the porous LSCF6428 layer had uniform thickness and showed excellent adhesion to the dense substrate. The oxygen flux of the surface modified membrane was improved by 30-60% with the maximum flux obtained was 0.86 mL cm-2 min at 800°C.