Abstract: The antioxidant effects of individual and combined three kinds of selenium including sodium selenite( SS),L-Se- methylselenocysteine( L- Se- MSC),Se- enriched yeast( SEY),Vitamin E,anthocyanin extracts of purple carrots were determined by DPPH radical scavenging activity,Fe~(3+) reducing power and ABTS radical scavenging activity. Isobolographic analysis was used to calculate the actual antioxidant value in IC_(50 mix) and evaluate the synergistic antioxidant effect of individual and combined different forms selenium,Vitamin E and purple carrot extract. The results indicated that L- Se- MSC and SS possessed low antioxidant activity in vitro antioxidant model,while SEY possessed high antioxidant activity which exhibited synergistic effect with Vitamin E,anthocyanin extracts of purple carrots.In the same model,different combinations had different effects.The best ratio in DPPH model was V_Emix)∶ Ant_(mix)∶ SEY_(mix)= 4∶ 1∶ 1,in the Fe~(3+) model,the best one was V_Emix)∶ Ant_(mix)∶ SEY_(mix)= 1∶ 4∶ 1 and V_Emix)∶ Ant_(mix)∶ SEY_(mix)= 1∶ 1∶ 1 was the best one in ABTS+·model. In the same combination,different factors showed different effects. The combination of selenium yeast,vitamin E,and anthocyanin extracts of purple carrots had synergistic antioxidant effects.