During cation exchange treatment of low rank coals, carboxyl groups in the coal structure are exchanged with the desired cations. In this study, the liquefaction reactivity of cation (Fe2+, Co2+, or Ni2+)-exchanged Adaro sub-bituminous coal in tetralin solvent with sulfur promoter was compared with the reactivity of demineralized coal Plus the oxide, sulfide, or oil soluble complex (metallocene or metal carbonyl) of any one of Fe, Co, Ni, Mo, or W. The findings are as follows: (1) Upgrading of demineralized coal is not enhanced by addition of oxide or sulfide of any one of Fe, Co, Ni, Mo, or W because these metal powders do not easily disperse into coal macromolecules during liquefaction. (2) In comparison with liquefaction of demineralized coal plus the complex of Co or Ni, liquefaction of Co- or Ni-exchanged coal significantly increases by catalytic activity of sulfurized Co or Ni. (3) Catalytic activity of exchanged Co or Ni is almost equal to that of Mo or W derived from the respective carbonyl complex.