The work aims to study the influence of chlorine dioxide gas treatment on the quality maintenance effect of Korla Pears in the later storage period. Under the condition of (0±0.5)℃, Xinjiang Korla Pears (experimental material) were treated with chlorine dioxide gas with concentrations of 0, 130.43, 260.86 and 391.29 mg/m3. The experimental results showed that, the treatment with chlorine dioxide gas of suitable concentration could effectively reduce the weight loss rate of the pears, maintain good color and luster, effectively slow down the pears' soluble solids, titratable acid, Vc, and the consumption of chlorophyll content, enhance peroxidase (POD) activity, and inhibit polyphenol oxidase (PPO) activity. The treatment with mass concentration of 130.43 mg/m3 had the best effect. Treating Korla Pears with chlorine dioxide is beneficial to maintaining fruit quality and thus extending shelf life.