Antioxidant activity of Butea monosperma flowers was essayed through some in vitro models such as the radical scavenging activity using 2,2-diphenyl-1-picryl hydrazyl (DPPH) assay, reducing power assay, nitric oxide scavenging activity and antioxidant capacity by phosphomolybdenum method. The n-butanolic and ethyl acetate fractions were obtained by liquid-liquid partition from methanolic extract of Butea monosperma flowers. The n-butanolic fraction showed the highest scavenging activity and reducing power followed by ethyl acetate fractions in a dose dependent manner. Results were compared to standard antioxidants such as ascorbic acid. The present study reveals that fractions of Butea monosperma flowers posse strong antioxidant activity and it might be useful in the management of various pathophysiological conditions associated with oxidative stress.