Reversed-phase high performance liquid chromatography (RP-HPLC) was used at various temperatures (room temperature to 70°C) to separate Polycyclic aromatic hydrocarbons (PAHs) on silica ODS using proportions of organic modifier in the mobile phase. The selectivity and retention patterns of four PAHs (naphthalene, fluorene phenanthrene and fluoranthene) were investigated. Successful separations with high column efficiencies were achieved at high column temperatures. Selected separation conditions for all PAHs compounds at elevated temperature were: mobile phase: acetonitrile-water: 40-60 v/v, column: Hypersil ODS, 51.1, (4.6mm I D x 100mm), flow rate: 2.5 mL/min, UV wavelength at 254 nm.