Objective:To evaluate the in-vitro antioxidant and antimicrobial activity of cvcloart-23- ene-3β,25-diol(called as B2) isolated from stem bark of Pongamia pinnata.Methods:In vitro antioxidant activity of B2 was determined by methods for determination of Dl’PH radical scavenging,reducing power,superoxide anion radical scavenging,hydroxyl radical scavenging, hydrogen peroxide scavenging,metal chelating and nitric oxide radical scavenging at the doses of 20.40.60.80 and 100μg/mL,respectively.3 -tocopherol with same concentration was used as a standard antioxidant.In vitro antimicrobial activity of B2 was determined by cup plate method in different concentration range of 10-100μg/mL.Results:The results indicated that dose dependent%reduction against DPPH radical,reducing power,superoxide anion radical scavenging,hydroxyl radical scavenging,metal chelating,hydrogen peroxide scavenging and nitric oxide radical scavenging by B2 andβ-tocopherol.Conclusions:It is concluded that cycloart 23-ene-3β,25 diol(B2) showed dose dependent antioxidant activity.B2 showed more DPPH radical scavenging,reducing power,superoxide scavenging,hydroxyl radical scavenging, metal chelating scavenging,hydrogen peroxide radical scavenging and nitric oxide radical scavenging activity thanβ-tocopherol and in case of antimicrobial activity B2 exhibited broad-spectrum activ ity against bacteria and strong activity against yeast type of fungi. Objective: To evaluate the in vitro antioxidant and antimicrobial activity of cvcloart-23-ene-3β, 25-diol (called as B2) isolated from stem bark of Pongamia pinnata. Methods: In vitro antioxidant activity of B2 was determined by methods for determination of Dl’PH radical scavenging, reducing power, superoxide anion radical scavenging, hydroxyl radical scavenging, hydrogen peroxide scavenging, metal chelating and nitric oxide radical scavenging at the doses of 20.40.60.80 and 100 μg / mL, respectively. 3 -tocopherol with same concentration was used as a standard antioxidant. In vitro antimicrobial activity of B2 was determined by cup plate method in different concentration range of 10-100 μg / mL. Results: The results indicated that dose dependent% reduction against DPPH radical, reducing power, superoxide anion radical scavenging, hydroxyl radical scavenging, metal chelating, hydrogen peroxide scavenging and nitric oxide radical scavenging by B2 and beta-tocopherol. Conlusions: It is what that cycloart 23- ene-3β, 25 diol (B2) showed dose dependent antioxidant activity. B2 showed more DPPH radical scavenging, reducing power, superoxide scavenging, hydroxyl radical scavenging, metal chelating scavenging, hydrogen peroxide radical scavenging and nitric oxide radical scavenging activity than β-tocopherol and in case of antimicrobial activity B2 exhibited broad-spectrum activ ity against bacteria and strong activity against yeast type of fungi.