Microwave-assisted heterogeneous catalytic oxidation of CO over ABO(3) type perovskite oxides (A: La; B: Mn, Fe, Co) was carried out and the factors controlling the catalytic properties were investigated. The heating behavior of perovskite oxides depended on the physical state of catalyst particles and catalyst compositions. Catalytic activity of the perovskite oxide decreased in the order of LaCoO3 > LaMnO3 > LaFeO3 under conventional heating, although LaMnO3 exhibited similar activity to LaCoO3 under microwave heating. The partial substitution of A site cation La by Sr enhanced the heating and catalytic properties under microwave heating conditions. Catalytic properties of the perovskite oxides under microwave heating were compared with those under conventional external heating. (C) 2015 Elsevier B.V. All rights reserved.