Silver nanoparticles (AgNP) have found prominence in different fields such as medicine, catalysis, nanoelectronics, textile field, pollution and water treatment due to their unique attributes. Applications of AgNP are increasing rapidly in the medical purpose including drug delivery, treatment, diagnosis, medical device coating. Various chemical and physical methods are used to synthesize the AgNP conventionally. However, these processes are expensive and also have side effects. To solve these problems by modification in synthesis process for safer and more efficiency, synthesis of biogenic AgNP from plant extract, known as Green Nanotechnology, have come to play a very crucial role, In this study, we have reported the green synthesis of AgNP using Ocimum sanctum (Tulsi) leaf extract, which act as reducing agent as well as capping agent. Synthesized AgNPs were characterized and their antibacterial and anticancer activities were observed. The development of brown color by the addition of Tulsi signifies the formation of silver nanoparticles. UV-Vis absorption spectroscopy, XRD and zeta potential were applied to estimate the quantitative formation of silver nanoparticles. FTIR analysis was used to reveal that the AgNPs were stabilized by eugenols, terpenes, and other aromatic compounds present in the leaf extract. The antimicrobial and anticancer properties of AgNPs were assessed by various in vitro cellular assays. Our present study confirms that AgNP can be used as a dual therapeutic option for combating pathogenic microbial strains as well as hepatocellular cancer.