Abstract: In this paper we have calculated various polyhedral skeletons of the transition metallic heteroboranes,Fe_nB_6-n(n=0,1,...,6)by using the Hoffmann's program of EHMOmethod,verified and discussed the structural rule of the thansition metllic heteroboranes proposed by us.BMO+NBMO=4n¹+9n₂-Fwhere BMO+NBMOstands for the number of valence bonding and non-bonding molecular orbitals,n₁ and n₂ are respectively the numbers of main group and transition metal atoms in the skeleton of a heteroboranes,and Fis the number only depending on the geometry of the skeleton,and discussed some properties of the skeletons.As example,we also calculated C₆H₅FeB9C₂H₁₁ and its skeleton by the same method to compare each other.