Among these fermentation medium cultures, the maximal antioxidant activity was observed in unpolished rice combine with potato extract medium culture, with EC50 was 0, 1 mg cao / ml, 32 times lower when compared with control medium. Conclutions: Monascus purpureus grew on medium contain unpolished rice combine with potato extract reach the highest antioxidant effect show through the test of scavenging ability on DPPH.