Abstract: The present study aims to investigate the methanolic extract of different plant parts of, Datura stramonium Linn (family Solanaceae) for their antioxidant activity. The maximum DPPH scavenging activity of extract and standard was found to be 92.3% at 1000 μg mL-1 and 92.8% at 1000 and 512 μg mL-1, respectively. The IC50 of the Methanolic extract of Datura stramonium and standard was found to be 39.48 and 42.0 μg mL-1, respectively. The maximum superoxide scavenging activity of plant extract and standard was found to be 73.1 and 83.4% at 128 μg mL-1. The IC50 value of plant extract and standard was found to be 28.45 and 42.32 μg mL-1, respectively. Maximum chelating of metals ions at 1000 μg mL-1 of extract and standard was found to be 63.9 and 89%, respectively. The IC50 values of plant extract and standard was recorded as 26.45 and 58.41 μg mL-1, respectively. The maximum ABTS scavenging activity of plant extract and standard was found to be 84.5 and 79.2% at 256 and 128 μg mL-1, respectively. The IC50 value of plant extract and standard was recorded as 40.11 and 24.29 μg mL-1, respectively. The maximum nitric oxide radical scavenging activity of extract and standard was found to be 63.1 and 72.3% at 1000 and 512 μg mL-1, respectively. The IC50 value of the methanol extract and standard was found to be 35.85 and 29.34 μg mL-1, respectively.