Abstract: Possible equilibrium geometries of W_mC_n clusters are optimized by using density functional theory at B3LYP/LANL2DZ level.For ground-state structures,average binding energy,second difference in energy,HOMO-LOMO gaps and the Wiberg bond index are analyzed.With increasing tungsten atoms,structures of clusters transform from linear into planar,and then become three-dimensional structures.All spin multiplicity is not more than 5.Hybridization of carbon atoms enhanced stability of the clusters,but reduced chemical activity.And Wiberg of W-C is much stronger than that of W-W and C-C,so it is easier to form W-C bond in W_mC_n clusters.