In the present study, an attempt was made to investigate the oxidative stability of the various sesasme blended oils. Sesame blended oils were prepared by mixing sesame oil with various vegetalbe oils(soybean oil, corn oil, ricebran oil, rapeseed oil, cottonseed oil, and perilla oil) in a ratio of 3:7(w/w). Fatty acid composition and some of physico-chemical characteristics of the sesame blended oils and vegetable oils including sesame oil were determined before the oxidation experiments. The fatty acid compositions and the physico-chemical characteristics of the vegetable oils changed by blending the oils with sesame oil and the extent of change varied with the type of oil. Particularly, the iodine value of the vegetable oils decreased significantly by sesame oil blending. The sesame blended oils and the vegetable oils including sesame oil were oxidized at 45℃ for 25 days in a dark place, and at 35℃ for 12 days under the irradiation of incandescent electric lamp (40W). During the oxidation, some physico-chemical characteristics of the oils were determined to evaluate the oxidative stability. Based on the changes of peroxide values, the oxidative stability of the vegetable oils was improved by sesame oil blending.