The work aims to expand the use of chitosan (CS) in preservative coatings and provide theoretical support for research of aquatic product preservation mechanism. With chitosan (CS) modified by in-situ synthesis of nano-SiOx as the film-forming matrix, and lysozyme (LZM) and tea polyphenols (TP) as additives, the in-situ synthesis of nano-SiOx/LZM/TP-CS composite coatings was prepared by the tape-casting method. Shewanella putrefaciens, one dominant spoilage bacteria of aquatic products, was used as the antibacterial object to study the antibacterial properties of the coatings. Scanning electron microscope (SEM) was used to observe the changes of the micro morphology of the bacteria before and after being treated by the composite preservative coatings. The changes of conductivities, OD260, Na+/K+-ATPase and AKP enzyme activities of the bacterial suspension treated by the composite preservative coatings for a certain time were determined. The results showed that all the coatings exhibited antibacterial properties. The bacteria deformed after being treated by the coatings, and the conductivity, OD260, Na+/K+-ATPase and AKP enzyme activities of the bacterial suspension were significantly higher than those of the untreated samples during the same period. After CS was modified by nano-SiOx, the antibacterial property of the coatings was slightly improved, the bacteria collapsed in many places, and the conductivity, OD260, Na+/K+-ATPase and AKP enzyme activities of bacterial suspension were significantly increased. After adding LZM or TP, the antibacterial properties of the coatings continued to improve, and the antibacterial properties of the in-situ synthesis of nano-SiOx/TP-CS composite coatings were better. When LZM and TP were added to CS coating modified by nano-SiOx at the same time, the cell wall was dissolved and seriously damaged. The conductivity and OD260 of the bacterial suspension treated at the same time were the highest, and even the Na+/K+-ATPase and AKP enzyme activities were inhibited. Combined with previous research results, SiOx/LZM/TP-CS composite preservative coatings have good preservative and antibacterial properties, which can provide theoretical guidance and technical support for the application of edible preservative coatings.