Abstract: The abundant bioresources found in nature, including plants are used in the green synthesis of Silver nanoparticles. It offers an improvement over chemical and physical processes since it is less expensive and more environmentally friendly. This study aimed to synthesize silver nanoparticle using green method, characterization of silver nanoparticle using analytical techniques and to evaluate the antibacterial activity of synthesized silver nanoparticle. Psidium guajava L. leaf was collected, authenticated and extracted by water. A 1mM solution of silver nitrate was prepared. Afterwards, separate quantities of 1, 2, 3, 4, and 5mL of the plant extract were added to 10mL of silver nitrate to facilitate the synthesis of silver nanoparticles (AgNPs). The synthesized AgNps were characterized using UV/VIS Spectrometry, SEM analysis and FTIR analysis, also the antibacterial activity of AgNP at different concentrations against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa was evaluated using well diffusion method. The synthesized Silver nanoparticle were detected by UV/ Vis spectrophotometer with absorbance peak at 459 nm. SEM analysis showed that silver nanoparticles were crystalline aggregate in nature and the size of AgNP was estimated between 1 - 200 nm. The reduction of silver nanoparticles and presence of functional groups of plant extract was confirmed by FTIR analysis of silver nanoparticles. AgNPs synthesized from P. guajava leaf revealed antimicrobial activity against all selected bacterial species. The use of nanotechnology in therapy development is an incredibly exciting and rapidly advancing field, the potential benefits of these emerging technologies make them a highly promising avenue for future medical research and innovation.Abstract: The abundant bioresources found in nature, including plants are used in the green synthesis of Silver nanoparticles. It offers an improvement over chemical and physical processes since it is less expensive and more environmentally friendly. This study aimed to synthesize silver nanoparticle using green method, characterization of silver nanoparticl...Show More