Objective To explore the effects of different modified atmosphere packaging (MAP) treatments on the preservation of Dongkui bayberry during storage.Methods Dongkui bayberry from Shiping County, Yunnan Province is taken as the test object and stored in different MAP bags to determine and analyze the ripening, softening, and antioxidant properties during postharvest storage.Results Compared with the control group, during storage at 4 ℃, the combined treatment of 1-methylcyclopropene (1-MCP) + sulfur dioxide + poly (butylene itaconate) (PBI) physically activated fresh-keeping bags can effectively maintain the quality and high antioxidant properties of bayberry. After 14 days of storage, this combined treatment slightly increases the decay rate, inhibits the respiration, reduces the loss of quality, soluble sugar, and titratable acid, slows down the hardness decrease, and increases the relative conductivity, maintaining the quality of bayberry to an ideal degree. Additionally, the activities of polygalacturonase (PG), cellulase (Cx), and polyphenol oxidase (PPO) are inhibited. In the meantime, the activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX), and phenylalanine ammonia-lyase (PAL) in the fruits are significantly higher than those in the control group (P<0.05). Consequently, the production rate of superoxide anion is reduced, and the active oxygen metabolism level of bayberry is better maintained. Therefore, the storage period of fresh Dongkui bayberry is extended to 14 days.Conclusion The combined treatment of 1-MCP + sulfur dioxide + PBI MAP bag demonstrates the best storage effect on the ripening, softening, and antioxidant properties of bayberry.