The present study was carried out to the green synthesis of ZnO nanoparticles and investigation of its antibacterial activity. Rosa indica leaves is of considerable interest and is a well-known compound because of its show antioxidant, antidiabetic, anti-inflammatory, antimicrobial activities etc . In the present study focuses on the Green synthesis of ZnO nanoparticles by sodium hydroxide, Zinc acetate and biocomponents of leaves of Rosa indica in the reaction mixture was observed in the precipitate from, which proved the formation of ZnO nanoparticles. Further, the green synthesized ZnO nanoparticles were characterized UV-Vis spectrophotometer, XRD analysis, FTIR, DLS, SEM with EDX. this all analysis shows the confirm the nanoparticles .the ZnO nanoparticles show particles size 10nm through DLS analysis. Antibacterial activity of the ZnO nanoparticles was evaluated by testing against Gram-negative(E.coli) and Gram-positive (S.aureus) bacteria. The antibacterial activity of the Synthesized ZnO nanoparticles was found to be more effective against Gram-positive bacteria (S.aureus). [ABSTRACT FROM AUTHOR]