Abstract: In this study, zein was glycosylated via ultrasound-assisted Maillard reaction to prepare glycosylated films with varying reaction times (0~2.5 h). The physicochemical properties of these films were systematically characterized before their application as coating preservation materials to mitigate the postharvest quality deterioration of blueberries. The results indicated that the zein-glucose glycosylated film exhibited the highest degree of grafting, which established glucose as the preferred sugar source. With the extension of Maillard reaction time, the glycosylated films showed intensified browning and an increased grafting degree. The incorporation of hydroxyl groups into the zein molecular structure was confirmed, and the surface of glycosylated films displayed a porous and rough microstructure. Meanwhile, the hydrophilicity of glycosylated films was significantly (P<0.05) enhanced. The mechanical strength and antioxidant activity both initially increased and then decreased, reaching the optimal level at a reaction time of 2 h (ZG-MR-2h). At this point, the grafting degree of the ZG-MR-2h film was 18.26%, with solubility and swelling ratios of 23.63% and 49.38%, respectively. The tensile strength and elongation at break reached 19.07 MPa and 29.36%, while the DPPH and ABTS⁺ free radical scavenging rates were 48.64% and 50.24%, respectively. Blueberry preservation experiments demonstrated that ZG-MR-2h coating could significantly (P<0.05) reduce the weight loss rate and decay rate of fruits, maintain high fruit firmness, retard the decline in contents of soluble solids, anthocyanins, and vitamin C, and inhibit the reduction in sensory scores including color, firmness, wrinkling, decay degree, odor, flavor, and taste, thereby effectively retarding the deterioration of fruit quality. The combined analysis of electronic nose and GC-MS showed that ZG-MR-2h coating could significantly delay the attenuation of characteristic aroma components such as aldehydes, alcohols, esters, and terpenes in blueberries, while reducing the formation of spoilage odor substances such as acids, sulfides, and nitrogen oxides. This study will provide theoretical support for the development of a green coating preservation technology for blueberries based on glycosylated protein.