Abstract: Reaction behavior of Naomaohu (NMH) coal in tetralin was carried out under atmosphere of H₂. Hydrogen transfer in complex multi-phase system of direct coal liquefaction were discussed. The influence of phase transition process of iron-based catalyst on liquefaction performance was investigated using X-ray diffraction, saturate magnetization and scanning electron microscope. The results show that NMH coal presents good liquefaction performance at 420℃ and 17 MPa. Active phase Fe₇S₈ plays catalytic role during initial reaction and changes into nonactive phase-Fe₉S₁₀ and FeS later. High hydrogenation activity of catalyst and long residence time are beneficial to hydrogenation of preasphaltene and asphaltene into light oil. Catalyst promotes the activation of H₂ transferring to coal pyrolysis products and solvent. Catalyst promotes the hydrogen in solvent to transfer to coal pyrolysis products as well. The contribution to activated hydrogen from solvent is twice as that from H₂ in the condition of the experiment. Hydrogen transferring from H₂ to solvent changes little with temperature, pressure and time. Activated hydrogen from H₂ and solvent is proportional to the conversion of coal and asphaltene to oil and gas.