A new type emulsion explosive containing plenty of Fe and Mn elements was prepared for synthesis of nano-MnFe₂O₄ powders by detonation method. The collected detonation products were characterized by X-ray diffraction (XRD) and transmission electron microscope (TEM). The results indicate that spherical nano-MnFe₂O₄ powders with spinel structure were successfully synthesized by detonation of this kind of emulsion explosive,and that the impurities could be removed after the products are treated at 280 ℃ for 1 h.