Abstract: In this article, the influence of sulfur content on the direct liquefaction reactivity of long flam coals was studied in the laboratory autoclave. The experiment results indicated that the oil yield and the total conversion of all the coals increases at first, then decreases with the sulfur content increasing, the maximum value is 49.79 % and 86.38 % when the sulfur content is 6.65% and 4.37%, respectively. The gas yield and hydrogen consumption of all the coals except number 1 increased and the water yield almost did not change with the sulfur content increasing. The combined affect of sulfur and minerals in the coals and the hydrogen in the system can catalyze the direct liquefaction reactivity.