Polyphenol rich fraction from Amanita vaginata, a wild edible mushroom, was prepared to investigate its antioxidant activity and presence of various bioactive constituents. The fraction possessed 5 different types of components in a consequence of phenol> ß-carotene> flavonoid> lycopene> ascorbic acid. The extract was extremely good in hydroxyl radical scavenging (EC50= 0.01 mg/ml). EC50 values for rest four different antioxidant assays were between 1.2 mg/ml to 1.75 mg/ml. Thus the mushroom species can be used as an easily accessible source of natural antioxidants or in pharmaceutical industry.