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Green packaging film continuously gains attention attention nowadays. Efforts to improve it mechanical p roperties have been explored through nanotechnology. ZnO nanoparticles incorporation to biofilms was exp lored. Nano-ZnO was purchased from US Research Nanomaterials, Inc. with 80 - 200 nm diameters. Bionanocomposite was done by dispersing 1-3% (w/ w) nanoparticles of the total starch in water under ultrasonication and magnetic stirring. Ratios of 3:1:1:9 of starch, glycerine, acetic acid, and water were mixed. Solution was heated to 85C to gelatinize. It was casted to molders, dried at 23'C, and peeled. Control films were also prepared. Mechanical properties were tested using Universal Testing Machine. Chemical groups were obtained by Fourier Transform Infrared (FTIR). Antimicrobial assay against Escherichia coli, Staphylococcus aureus, and Aspergillus niger was performed. Analysis was done at least in triplicates. Average tensile stress of 443.97MPa with 171.09% elongation for control and 477.03MPa with 107.80% elongation for samples with 1% nanoZnO were recorded. Strength was statistically increased without varying appreciably the strain. Bands shifting ofC-H, CO, alkanes, alkenes, and hydroxyls groups were detected. FTIR suggested ZnO-bioplastic interaction. Zone ofinhibitions (ZI) were 25.06mm (E.coli), Omm (S. aureus), and Omm (A. niger) for control. Bioplastics with 1% nanoZnO had 26.04mm (E.coli), 25.28mm (S. aureus), and Omm (A . niger) inhibitions. Films with 3% nanoZnO had 26.47mm (E.coli), 25.49mm (S. aureus), and Omm (A. niger) inhibitions. Control films initially inhibit E. coli growth only. Films with nanoZnO exhibited antimicrobial activity against tested microorganisms except in fungi. Results revealed that nanoZnO improves the bioplastic mechanical strength. It further illustrated the market potential of ZnO nanobiocomposite films as green packaging material with protection against microbes.