Abstract:The blackcurrant fruit as the raw material，polysaccharide and the extract of water and alcohol were extracted by microwave-ultrasonic assisted extraction.The polysaccharides were characterized by IR.In vitro antioxidant systems；the antioxidant activity of extract on blackcurrant's marc was discussed.Such as：superoxide radical，hydroxyl radical，DPPH.The results showed that：the infrared signature showed that polysaccharide was α-pyranos.The polysaccharide or alcohol extract concentration was 0.8mg/mL，the scavenging rate of DPPH radical and hydroxyl radical was more than 90%，the extract of water was more than 80%.The polysac－charide scavenging rate of superoxide radicals was 60%，the extract of water and alcohol was more than 50%.As a result，there was significant antioxidant activity about the extractions and the development of the blackcurrant's marc has a bright future.