Recently,3d transition metal based antiperovskite compounds AXM3(A,usually main group elements; X,boron,carbon,or nitrogen; M,3d transition metal)have attracted considerable attentions due to lots of interesting properties,especially for the superconductivity found in MgCNi3.The Fermi level of MgCNi3 locates very close to a van Hove singularity,which leads large density of states at Fermi level(N(EF))and enhances the electron-phonon coupling; on the other hand,the large N(EF)also leads strong spin fluctuation.