Abstract: The chromatographic conditions were determined by gas chromatography-hydrogen flame ionization detector (GC-FID). The composition informations of monomer compounds in direct coal direct liquefaction naphtha were determined by comprehensive two-dimensional gas chromatography combined with time-of-flight mass spectrometry/hydrogen flame ionization detector (GC×GC-TOF MS/FID) analysis. The compounds were classified according to the z-value classification method, and a total of 5 racial compounds were obtained. The order of polarity from low to high were alkanes, monocycloalkanes, bicyclic alkanes, alkylbenzenes, and monocyclobenzenes. 13 aromatic compounds were detected in total, 12 compounds were alkylbenzenes, and 1 compound was indene. 128 monomer compounds were qualitatively and quantitatively identified by gas chromatography-time-of-flight mass spectrometry/hydrogen flame ionization detector (GC-TOF MS/FID). Most of them were cycloalkanes, and some of them were alkanes. Cycloalkane compounds were mostly isomers of cyclopentane and cyclohexane with side chains.