Hydrolysate was extracted from starfish Asterina pectinifera, the starfish Asterina pectiniferas were hydrolyzed with pepsin, neutrase and trypsin under their optimal conditions to obtain the hydrolysate, and the antioxidant activity of hydrolysate was detected by using electron spin resonance(ESR) spectroscopy The results indicated that the DPPH radical and hydroxyl radical scavenged ability increased with the increasing concentration of hydrolysate; at the concentration of 20 mg/mL, the clearance rate of pepsin group, neutrase group and trypsin group on DPPH radical were(5225±014)%, (6830±037)% and (4627±047)% respectively, and the rate of hydroxyl radical were(7261±017)%, (8182±079)% and (5677±028)% respectively.