Abstract: The extraction technology of total flavonoids from jackfruit seed powder was studied by four factors three levels orthogonal experiment. The results showed that the effect order of four factors on the extraction rate of total flavonoids from seed powder of jackfruit was：ethanol concentration > liquid ratio > extraction temperature > extraction time. The ethanol concentration had a significant effect on the total flavonoids extraction rate（ P<0.01）， the ratio of material to liquid，the extraction temperature and extraction time had significant effects on the total flavonoids extraction rate（ P<0.05）. When the ethanol concentration was 70%，the extraction temperature was 60℃，the extraction time was 50 min，the ratio of material to liquid was 1∶20，the optimum extraction process under the condition of water bath was reached. The extraction rate of total flavonoids from jackfruit seed powder under the best extraction process conditions reached 3.30%. The antioxidant activity of crude flavonoids from jackfruit seed powder was determined by DPPH method and salicylic acid method. The results showed that the scavenging rate of free radicals was more than 90% at 0.6 mg/mL，indicating that the flavonoids from jackfruit seed powder had strong antioxidant activity and had good application prospect. In actual production，the seed of jackfruit can be used as the source of antioxidants.