Abstract: Coal liquefaction products (CLP) with boiling point range 80—450℃ were analyzed by low—voltage high—resolution mass spectrometry (LVHRMS). The quantitative resuits of elemental analyses, carbon number distributions, average molecular weights,compound types, and aromaticity measured by Z value for CLP were obtained. 62 chemical structure classes and 441 molecular ions in CLP have been determined. The application possibility of LVHRHS, at the lower resolution (7,500) has been tested and discussed.