In this work, the quantitative estimation of fatty acids in sesame and perilla oil by high performance liquid chromatography (HPLC) was investigated. The analysis of fatty acids were separated by HPLC using a differential refractometer as a detector. With micro Bondapak $C_{18}FFAA$ column and acetonitril, chloroform and tetrahydrofuran mixture as a solvent. In the fatty acid compositions, sesame oil was composed mainly of linoleic and oleic acids 49.6 % and 34.7%. In perilla oil, the amounts of oleic, linoleic and linolenic acids were 13.6%, 14.5% and 63.8%, respectively.