The natural antioxidants such as ${alpha}-tocopherol$, NDGA, proply gallate and sesamol, and synthetic antioxidants, BHA were used to compare antioxidative effects of those antioxidants from tile physico-chemical properties and fatty acid composition changes in the soybean oil during storage. The oils were stored at $25^{circ}C$ for 2 weeks after heat treatment. Natural antioxidants were less effective than BHA but effect of ${alpha}-tocopherol$ was very similar to that of BHA. The order of antioxidative effect was BHA, ${alpha}-tocopherol$, NDCA propyl gallate and sesamol. The relative contents of linoleic acid and linolenic acid was decreased as the degree of oxidative rancidity was increased. whereas content of oleic acid and palmitic acid was increased. The content of linoleic acid and linolenic acid did not decreased by addition of BHA and ${alpha}-tocopherol$.