Co3O4 nanowires (NWs) arrays were successfully fabricated via a facile hydrothermal-annealing method. The component, structure and morphology of the Co3O4 NWs arrays were characterized. The slim Co3O4 NWs consist of interconnected nanocrystals and have a specific surface area of 26.6 m(2) g(-1). The obtained materials have exhibited an excellent catalytic performance on the thermal decomposition of ammonium perchlorate (AP). In addition, catalytic activities of the prepared Co3O4 mainly depend on the content of catalyst. Impressively, an addition of 9 wt% Co3O4 NWs arrays to AP exhibited the most significant catalytic effect in lowering the decomposition temperature from 404 to 288 degrees C, increasing the decomposition heat from 502 to 930 J g(-1) and decreasing the activation energy from 201 to 168 kJ mol(-1). Furthermore, the catalytic mechanism of the Co3O4 NWs arrays based on electron transfer processes was discussed.