Abstract: Abstract:In this paper, based on Tetra-n-butyl Titanate as raw material, nanometer TiO2 was prepared by solvent gel (Sol-Gel) method. Modified powder surface morphology and structure was inspected by SEM. Nanometer powder surface was modified with silane coupling agent (KH550, KH570 and A171, respectively). The surface structure and qualitative change of modified powder were observed by SEM, XRD and FTIR. Besides the oil-wet change degree value and dispersing situation in water, toluene and petroleum were detected. Using toluene as solvent, the modified powder and LDPE resin were mixed and then achieved antibacterial polyethylene composite film membrane through the way of flow delay. The modified nano TiO2 antibacterial agent/LDPE compound film antibacterial performance was measured with SEM and digital camera. The results showed that the best dispersion in toluene was KH570 modified powder. When 3% antibacterial powder added, the antibacterial properties of composite film were best. Its antibacterial rate reached 99.9%, which had the best antibacterial effect.