Abstract: China possesses enormous reserves of low-rank coal, and direct coal liquefaction is a key technology for converting low-rank coal into high-end oil products and alleviating the country's dependence on petroleum.The structure and reactivity of coal macerals are the primary factors determining liquefaction con-version efficiency and oil product quality. Different macerals exhibit markedly distinct reactivity in terms of the degree of aromatic condensation, the abundance of active bridge bonds, and the total content of oxygen-containing functional groups. Focusing on vitrinite, inertinite, and liptinite in coal, this paper systematically reviews the intrinsic relationship between their structural characteristics and liquefaction activity. On this basis, it highlights the liquefaction conversion efficiency of different macerals and the mechanisms of macromolecular covalent bond cleavage and free radical generation during liquefaction, and analyzes the possible interaction mechanisms among different macerals during co-liquefaction. Meanwhile, the effects of various reaction conditions on maceral liquefaction are examined, including reaction temperature and residence time, hydrogen pressure and hydrogen-donor solvents, catalysts, and mineral matter in coal. Increasing the temperature can accelerate bond cleavage, but excessively high temperatures intensify condensation and coke formation. Prolonging the residence time helps improve conversion, but there exists an optimal window for oil yield. High hydrogen pressure and high-quality hydrogen-donor solvents (e.g., tetralin) can effectively stabilize free radicals and inhibit their condensation. Iron-based catalysts enhance liquefaction efficiency by promoting hydrogen transfer and suppressing coking. Mineral matter in coal plays a dual role in liquefaction: pyrite promotes hydrogenation by generating the catalytic phase Fe???S, clay minerals exhibit a twofold nature of enhancing mass transfer while inducing condensation, and the influence of alkali and alkaline earth metals remains controversial. Future research should employ advanced experimental techniques and theoretical computational methods to deeply elucidate the relationship between structural differences of macerals, liquefaction mechanisms, and the matching of process conditions, thereby providing theoretical support for the selection of liquefaction feedstocks and the optimization of operating conditions.