Capillary gas chromatography-Fourier transform infrared spectrometry-gas chromatography retention indices (GC/FTIR-RI), combined with the linear relationship between retention value and boiling points for polycyclic aromatic hydrocarbons, performed the determination of the composition of heavy oil fractions in high-temperature coal tar. More than 70 and 61 compounds were separated and identified in heavy oil fractions F7(300-330 degrees C) and F8(330-360 degrees C) respectively. The results are useful in coal tar distillation processing and pollution monitoring when such compounds are present.