Abstract: The influences of temperature, H₂ pressure, hydrogen donating capabilities and catalyst on the hydroliquefaction of Hongliulin coal under mild conditions were investigated in this paper. The results showed that in the range of 370—390 ℃, higher reaction temperature could promote the pyrolysis reaction of coal; while in the range of 390—430 ℃, higher reaction temperature could promote the secondary cracking of heavy products. With the increase of reaction temperature, the reaction pressure should be increased to match the reaction temperature. Moreover, compared to coal liquefaction under mild condition with recycle solvent and Fe catalyst, the effect of Fe catalyst on the liquefaction performance with methylnaphthalene was slight, which could be ascribed to the weak hydrogen transfer ability of methylnaphthalene. Fe catalyst had a little effect on liquefaction performance with tetralin as solvent. It could be due to that tetralin was a good hydrogen donor solvent which dissociated a large amount of activated hydrogen, which could stabilize most of the free radicals produced from Hongliulin coal pyrolysis. Additionally, with the addition of Fe catalyst, the activated hydrogen produced from H₂ is more than that needed for Hongliulin coal liquefaction process. Furthermore, the addition of alkali catalyst to Fe catalyst could promote coal conversion, oil production and H₂ consumption, while reducing water production. It could be ascribed to the prominent synergistic effect between alkali catalyst and Fe catalyst in Hongliulin coal hydroliquefaction. The synergistic effect could promote the hydrolyzation of oxygen-containing moieties (such as carbonyl groups and ether bonds) and the depolymerization of macromolecular structures.