Abstract: A real boiling point distillation apparatus was used to cut the fractions of Baishihu coal liquefied oil. The fraction below 170 ℃ was taken as the catalytic reforming feedstocks of hydrorefining. Meanwhile, the sulfur and nitrogen compounds in liquefied crude oil and refined oil were analyzed and characterized by GC-SCD and GC-NCD to study the transformation rule of sulfur and nitrogen compounds in hydrofining process. The results show that the sulfur compounds in liquefied crude oil are mainly thiophene compounds and mercaptan, which disappear after hydrorefining, and the removal rate of benzothiophenols is lower than that of thiophene compounds. Nitrogen-containing compounds in liquefied crude oil are mainly aniline compounds and indole compounds. After hydrorefining, all indole compounds are basically removed. Aniline and quinoline compounds belong to basic nitrogen-containing compounds, and are the main nitrogen-containing compounds remained in refined oil with a content of 1.61 mg/kg.