Abstract:The purple cabbage as raw material，the anthocyanin was extracted by ethanol water extraction method.The appropriate range of process parameters of the extraction of anthocyanin from purple cabbage was determined through single factor test，and then the best extraction process was determined by orthogonal test.The results showed that the optimum conditions of anthocyanins extraction from purple cabbage was pH=1，extraction temperature 50℃，material liquid ratio 1∶40 （g/mL），extraction time 2.5 h，ethanol concentration 60%.Under these conditions，the anthocyanin content could be up to 4.530mg/g.The DPPH·scavenging activity was also studied to research the scavenging ability of anthocyanins in purple cabbage.The results showed that the higher the content of anthocyanin in the extract，the bigger the scavenging effect of DPPH·.