Abstract: Five brown coal samples different in macro-lithotype and micro-maceral from Huolinhe area are tested in two types of measurements,such as liquefying with hydrogen and activity test.To understand the liquefying properties and differences among different maceral groups,different macerals and sub-macerals of huminite,the differences of conversion rates are analyzed,as well as the remains after activity test are observed under microscope,fluoroscope and scanning electron microscope.This kind of differences suggests that the different brown coals,which are different in maceral composition,are of different conversion rates during liquefying with hydrogen.And a few samples basically composed of huminite are different in conversion rates.