In this paper, MgCNi3 microparticles have been first synthesized via a solid-state route through the reaction of metallic sodium, magnesium chloride, and nickelocene in a stainless steel autoclave at a relatively low temperature of 700 degrees C. The reaction temperature required for MgCNi3 microparticles preparation in our method is much lower than that used in the reported methods. The as-obtained MgCNi3 microparticles are investigated by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The magnetic measurement shows that the superconducting transition of the as-obtained MgCNi3 microparticles occurs at about 8.0 K.