The present study focuses on the microbial synthesis of zinc oxide nanoparticles (ZnO NPs) and evaluating the antimicrobial property on foodborne pathogens. The bacterial strain, Acinetobacter schindleri SIZ7 was isolated from the waste filling area of Sivakasi, Tamil Nadu, India. The biogenic synthesis of ZnO NPs was carried out at room temperature and under suitable, eco-friendly environment using culture supernatant of A. schindleri. The physico-chemical properties exhibited by the biogenic ZnO NPs were characterised using UV-Visible Spectrophotometry, Energy dispersive X-ray spectroscopy (EDS), High Resolution Transmission Electron Microscopy (HRTEM), Fourier Transformed Infrared spectroscopy (FTIR) and Thermogravitometric Analysis (TGA). The synthesized ZnO NPs are polydispersed and spherical in shape. The antimicrobial activity of ZnO NPs was investigated against foodborne pathogens, Staphylococcus aureus (MTCC 96), Escherichia coli (MTCC 739), Vibrio parahaemolyticus (MTCC 451) and Salmonella enterica (MTCC 9844). The prepared ZnO NPs exhibited strong antimicrobial activity against E. coli and S. enterica with a minimum inhibitory concentration of 100µg ml-1. Thus, the bacterial strain Acinetobacter schindleri SIZ7 could be used for simple, extracellular, non-hazardous and efficient synthesis of antimicrobial ZnO NPs.