Abstract: Bacterial growth can shorten the shelf life of food and exert a negative effect on human health, therefore it is of great importance to conduct research on anti-bacterial films. Herein, the γ-aminopropyltriethoxysilane coupling agent (KH550) was used to modify nano-zinc oxide, and the modified nano-zinc oxide (m-ZnO) was melt-blended with nylon 612 (PA612) to prepare m-ZnO/PA612 nanocomposite, followed by the fabrication of the antibacterial film through extrusion film casting process. The FTIR was used to characterize the nano-zinc oxide before and after the modification, which proved that KH550 was successfully grafted onto the nano-zinc oxide. Through SEM, DSC, TGA, plate counting method, and other test methods, the dispersibility of nano-zinc oxide and the crystallization performance, thermal performance, and antibacterial properties of composite materials were studied. The results show that the m-ZnO is well dispersed in the PA612 matrix. The m-ZnO can be used as a nucleating agent to increase the crystallinity of PA612. When the content of m-ZnO is 2wt%, the crystallinity is increased by 4.1%. Moreover, the m-ZnO exhibits a reinforcing effect on PA612. When the addition amount of m-ZnO is 2wt%, the tensile strength of the m-ZnO/PA612 nanocomposite film is 15% higher than that of pure PA612. The presence of m-ZnO gives PA612 antibacterial properties. m-ZnO/PA612 nanocomposite film has a good inhibitory effect on Escherichia coli and Staphylococcus aureus. With the increase of m-ZnO content, the antibacterial rate increases, when the mass fraction of m-ZnO is 4wt%, the antibacterial rate against Escherichia coli is 93.25%, and the antibacterial rate against Staphylococcus aureus is 91.03%.