Abstract: In order to optimize the microenvironment of modified atmosphere packaging (map) and evaluate its effect on the quality of chilled duck meat, enhance its preservation effect and prolong the shelf life of chilled duck meat, this study investigated the effects of different gas ratios on the quality of chilled duck meat with the total number of colonies, volatile base nitrogen, sensory evaluation as the index, based on the design of simplex-lattice point. The regression model was further established based on the total number of colonies and TVB-N values on the 7th and 9th day of storage, and the optimal air-regulation ratio was analyzed and verified. The results showed that 53%O₂+47%CO₂ was the optimal air-regulation ratio of chilled duck. Under this condition, 1/2 volume ratio and 4 ℃ storage temperature could keep the second-order freshness of chilled duck meat on the 10th day. In conclusion, the suitable modified atmosphere packaging microenvironment can effectively inhibit microbial growth and reproduction, reduce TVB-N production and improve sensory quality, which is helpful to extend the shelf life of chilled duck meat.