Perovskite-type LaCoO3 was prepared by stearic acid solution combustion method and characterized by XRD, DSC-TG, and XPS techniques. The catalytic activities of LaCoO3 for HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) thermal decomposition were investigated. ne as-prepared LaCoO3 shows higher activity than the calcined one. This could be due to higher concentration of surface-adsorbed oxygen and hydroxyl species as well as higher BET surface area of the as-prepared LaCoO3.