Abstract: The chemisorption of benzene on the Rh(111) surface is calculated using DVX_a method. The electronic structure, the ground states valence levels, Mulliken overlap populations, and the density of states (LDOS and TDOS) of the adsorption system C_6H_6/Rh_6(111) are obtained. The results of DV-X_a calculations indicate that the adsorbed benzene structure is unpertured from its stable gas-phase structure, is π-bonded to the Rh surface with ring plane parallel to the metal plane, and has a C_(3ν)(σ_d) bonding symmetry. We also discuss the charge transfer between adsorbate and substrate. The π electrons of benzene transfer to the empty d orbitals of Rh, so is resonance stability decreases and is easy to be hydrogenated. The results of TDOS are in agreement with UPS, supporting the LEED structural analysis. From figure 3, it can be found that the two peaks at 5—6 eV and 7—9 eV under Fermi level (E_F) move to left by about 0.5 eV in the process of adsorption, which are mainly contributed by the 2π and 1π orbiatls of benzene respectively and are widened, and the peaks at 2 eV and 4 eV over Fermi level also move to left, which are contributed by the empty d orbitals of Rh.