Hierarchical flower-like cobalt tetroxide (Co3O4) was successfully synthesized via a facile precipitation method in combination with heat treatment of the cobalt oxalate precursor. The samples were systematically characterized by thermo gravimetric analysis and derivative thermo gravimetric analysis (TGA-DTG), X-ray powder diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and N2 adsorption-desorption measurements. The results indicate that the as-fabricated Co3O4 exhibits uniform flower-like morphologies with diameters of 8∼12 μm, which are constructed by one-dimensional nanowires. Furthermore, catalytic effect of this hierarchical porous Co3O4 on ammonium perchlorate (AP) pyrolysis was investigated using differential scanning calorimetry (DSC) techniques. It is found that the pyrolysis temperature of AP shifts 142 °C downward with a 2 wt% addition content of Co3O4. Meanwhile, the addition of Co3O4 results in a dramatic reduction of the apparent activation energy of AP pyrolysis from 216 kJ mol-1 to 152 kJ mol-1, determined by the Kissinger correlation. The results endorse this material as a potential catalyst in AP decomposition.