The nanoscale dimension harbors dynamic physiochemical properties quite different from those of bulk counterpart relative to its size and large surface area to volume. Despite its wide application, research on fabrication using eco-friendly agents had been a major breakthrough in gaining control over size. Gallic acid, a phytochemical compound embodies characteristic features for an efficient reducing and capping agent. Silver nanoparticles (AgNPs) were synthesized using gallic acid and its biomedical application (antibacterial and antiproliferative activity) validated. Aqueous chemical reduction method was used to synthesize AgNPs and characterized by UV-vis spectrophotometer, X-ray diffraction and microscopic analyses. The antimicrobial susceptibility of AgNPs was tested using Kirby Bauer’s disc diffusion method and the anti-proliferative effect on HEp-2 cells by MTT dye reduction assay. AgNPs were synthesized rapidly in less than a minute with narrow peak showing λmax at 424nm, with crystalline nature and uniformly dispersed spherical shaped particles of size < 30nm. The antibacterial study of AgNPs revealed significant susceptibility toward a panel of Gram positive and Gram negative clinical isolates at all concentrations (10μg, 20μg and 30μg) on par with antibiotics. Further, the AgNPs showed potent antiproliferative activity on HEp-2 cells with IC50 < 1mg/mL concentration accompanied by morphological disturbances and membrane damage. The strong affinity toward intracellular proteins and thiol formation accounts for its toxicity which may further be extended for varied biomedical applications as a broad spectrum therapeutic agent.