Abstract: The effects of nitrogen filling preservation on the shelf life of first-class soybean oil products were investigated with the acid values, peroxide values and oxidative induction time as evaluation indices. Under the storage conditions of 20 ℃ and 40 ℃, it was compared with soybean oil of adding tertiary butylhydroquinone（TBHQ） group and blank group, and then the indices were determined every 3 months within the shelf life of18 months. Results showed that nitrogen filling preservation presented no obvious inhibitory effects on acid values of first-class soybean oil under 20 ℃ and 40 ℃ storage conditions, while better inhibited the increase of peroxide values and significantly enhanced the antioxidant capacities, and could effectively prolong the shelf life of first-class soybean oil products.