Chromatographic patterns of fuel oils such as kerosene. diesel oil, and sand oil were compared by supercritical-fluid chromatography (SFC) on an ODS silica gel column using fluorescence detector (FD), UV-absorption detector (UV), and flame-ionization detector (FID). The quartz FD cell in a square-pillared shape with square cross section was made and used to selectively detect polyaromatic hydrocarbons in fuel oils. The chromatographic profiles simultaneously obtained by FD, UV, and FID differed according to the properties of the components in the fuel oils.