A facile and rapid microwave-assisted combustion method was developed to synthesize the nanocrystalline Co3O4. The Study suggested that application of microwave heating to produce the homogeneous porous Co3O4 was achieved in a few minutes. The structure and morphology of the as-prepared nanocrystalline Co3O4 were investigated by means of X-ray diffraction (XRD), Fourier transform infrared spectra (FTIR), Raman spectra, UV-vis absorbance spectra and scanning electron microscopy (SEM). The XRD, FTIR and Raman spectra confirmed the formation of spinel structural Co3O4, and the SEM results indicated the porous surface characteristic of the products. Magnetic measurement was carried out using a vibrating sample magnetometer (VSM). The field dependence of the magnetization at room temperature showed a tiny hysteresis loop with a coercivity of 56.7 Oe. (C) 2009 Elsevier B.V. All rights reserved.