Green synthesis of silver nanoparticles (AgNPs) is very safe and eco-friendly to the environment as well as human. Plants provide a better platform for nanoparticles synthesis as they are easily available, safe, eco-friendly and free from toxic chemicals as well as provide natural capping agents. Secondary metabolites are the reducing agents in the synthesis of silver nanoparticles. In the present study, the medicinal plant Barringtoniaacutangula leaf extract was used as reducing agent. The presence of phytoconstituents of Barringtoniaacutangula was analyzed. The formation of silver nanoparticles was confirmed by color change and the characterization was done by UV-Vis, FTIR and SEM. The maximum absorbance of silver nanoparticles was attained at 435 nm wavelength. Protein molecules are act as capping agents of silver nanoparticles was suggested by FTIR. Size of the silver nanoparticles above 100nm which were detected by SEM analysis. The antibacterial activity of silver nanoparticles also reported on two species such as Escherichia coli and Staphylococcus aureusby well diffusion method. Antioxidant analysis of silver nanoparticles was done and the EC₅₀ value was determined. The EC₅₀ value of reducing power method is 0.813 mg/ml and total antioxidant capacity is 1.95mg/ml. The in vitro anticancer activity of silver nanoparticles was done by MTT assay on two cell lines such as HeLa (Human cervical carcinoma) and MCF-7 (Human breast adenocarcinoma) and the IC₅₀ value calculated. For HeLa cell line, the IC₅₀ value was obtained as 45.4 µg/ml and the IC₅₀ value of MCF-7 is 5.6µg/ml.