The oxygen permeation performance of perovskite La_0.6Sr_0.4Co_0.2Fe_0.8O_3−δ (LSCF) hollow fibre membranes was enhanced by surface modification via coating of a Ba_0.5Sr_0.5Co_0.9Nb_0.1O_3−δ (BSCN) porous layer. The hollow fibres were characterized by XRD, SEM and EDS elemental mapping and tested for air separation. Experimental results revealed that the BSCN porous layer had significantly improved the oxygen permeation flux of the coated LSCF hollow fibre membranes. Operated at 950 °C and under the oxygen pressure gradient of the air/sweep gas, the maximum oxygen permeation flux of 1.92 mL cm⁻² min⁻¹ was achieved after the hollow fibre membrane was coated by a BSCN porous layer on both outer and inner surfaces. In addition, the modified membrane showed high oxygen permeation stability under the investigated operational conditions.