The preparation and oxygen permeability of Pr(0.9)AE(0.1)Al(1-x)M(x)O(3) system, where AE=Ca or Sr; M=Co or Fe, have been studied. For Pr0.9Ca0.1Al1-xFexO3 solid solution having an orthogonal structure, an oxygen flux density of 4.6 x 10(-6) mol cm(-2) s(-1) was attained for x=0.8 in a methane conversion test at 1000 degreesC, by virtue of the enhancement of p-type conductivity by Fe-doping. In addition, Pr0.9Sr0.1Al0.2Fe0.8O3 with a membrane thickness of 160 mum exhibited an oxygen flux density of 8.2 x 10(-6) mol cm(-2) s(-1) at 1000 degreesC with the CH4 conversion and CO selectivity of 12% and 93%, respectively. (C) 2004 Elsevier B.V. All rights reserved.