Abstract: Coal liquefaction residue was fast pyrolyzed in a fixedbed reactor and slow pyrolyzed in thermal blance under N2 atmosphere. The influence of final temperature, residence time and particle size on char property was examined. It is found that final temperature and reside time are the dominant factors on flash pyrolysis. With the final temperature increasing, the char yields decrease and the char becomes crisper and less reactive. Less char yields and more porous char are obtained as the residence time becomes longer. At the same time, char yield reduces as the residual particle size becomes smaller in a large size range.