Abstract: To study the effect of edible oil contained DHA on the antioxidant activity of liver,this paper selected96 early weaning SD male rats(80±10) g,which were divided into 8 groups based on the random number.Table the negative control group(mixing ratio of soybean and peanut oil),positive control group(DHA algae oil),250,500,750 mg DHA were seperately added to 60 g soybean oil,peanut oil,with low,medium,high dose DHA were treatment group.According to the dosage of 1 m L oil per 100 g weight a day and after feeding for 4weeks and 8 weeks respectively,the SOD activity,MDA content and ACh E in the liver tissues of SD rats were detected. The results showed that the SOD activity of liver tissue in middle dosage of DHA group was significantly higher than that in negative control group,the MDA content was significantly lower than that in positive control group and the ACh E had no significant difference. The SOD activity in high dose of DHA group was significantly lower and the MDA content was significantly higher than that in negative control group,positive control group,and the ACh E also had no significant difference. While the other groups had no significant difference in ACh E,SOD activity and MDA content. Appropriate supplement of DHA could enhance the rat body's antioxidant capacity,but the excessive DHA will bring a negative effect.