Abstract:The yield of polysaccharide from Crocus sativus petals was 3.75% by water extraction and alcohol precipitation. The purity of crude polysaccharide was 68.34%, measured by anthrone-sulfuric acid method and DNS method. The antioxidant activity in vitro of crude polysaccharide was also determined. The results showed that crude polysaccharide exhibited certain antioxidant activity with the ORAC value of 0.572 μmol TE/mg, and had effect on scavenging ABTS+, DPPH and hydroxyl radical with the half elimination concentration (EC50) of 76.26 μg/mL, 165.5 μg/mL and 880.4 μg/mL respectively.