Abstract: The effects of Ammonium Molybdate catalyst were studied by using resonance agitation reactor during coprocessing Yangcun bituminous coal and Shengli residue with Tetralin as solvent under the hydrogen pressure of 7.0 MPa (ambient temperature). The results show that the catalyst not only increase coal conversion, but also promote convertion of preasphaltene benzene soluble products at low temperature (390 ℃). Coal conversion, Benzene soluble product yield and preasphaltene yield is lower with catalyst than without catalyst at high temperature (480℃). It means the catalyst can not resist the polycondension in the reaction system having hydrogen donor solvent at high temperature (480 ℃). Polycondension reaction increases rapidly with the increasing of the reaction temperature and reaction time at high temperature.