Abstract: Zinc oxide (ZnO) nanoparticles were fabricated by green process in presence of aqueous extract of Watermelon rind. High Performance Liquid Chromatography technique was used to assess the biomolecule content of the aqueous extract prepared from watermelon rind. Citrulline an essential amino acid present in watermelon rind was found to act as capping agent for fabrication of ZnO nanoparticles. The shapes of produced ZnO nanoparticles were found to be anisotropic with few nano rods which were confirmed by TEM analysis. The prepared ZnO nanoparticles were used as antimicrobial agent against pathogens. Higher activity was found against S. paratyphi B strains. Further, the ZnO nanoparticles were assessed for its heavy metal removal capacity from aqueous solution. The results suggest that watermelon rind can be a potential precursor for fabrication of ZnO nanoparticles with versatile applications.