Abstract: In this research, the effects of UF membranes with different MWCO (100, 30 and 10ku) on the clarification and the antioxidant activity of pomegranate juices were investigated, in order to select the optimal ultrafiltration membrane used to producing the clarified pomegranate juice with high antioxidant activity. The results showed that ultrafiltration membranes with MWCO of 30ku presented a better clarification effects than other membranes, and could retain 80% of the phenolic compounds, anthocyanins and VC in pomegranate juices and 84% of its radical DPPH scavenging activity and the FRAP. So it was suggested that ultrafiltration membranes with MWCO of 30ku was applied in the clarification of pomegranate juices with high antioxidant activity.