Abstract: To enhance the drying efficiency and quality of vacuum pulsation-dried chili peppers and to obtain the optimal pretreatment method, this study used ultrasonic, ultrasonic combined with blanching, and ultrasonic combined with freeze-thawing for the pre-drying pretreatment of chili peppers and analyzed the drying characteristics, physicochemical properties, and volatile composition of vacuum pulsation-dried chili peppers. The results showed that all the pretreatments effectively shortened the drying time, reduced the energy consumption of vacuum pulsation drying of chili peppers, and improved the physicochemical quality and flavor of the samples, and the ultrasonic combined with blanching had the best effect. Compared with the control samples, ultrasonic combined with blanching samples shortened the drying time by 29.15%, reduced energy consumption ration by 39.19%, retained capsorubin reached 100%, increased the contents of capsaicin, dihydrocapsaicin, vitamin C, and total phenols by 28.68%, 31.46%, 10.10%, and 68.90%, respectively, increased DPPH radical scavenging capacity and total antioxidant capacity by 14.11% and 70.45%, respectively, and had the best physical properties improvement and volatile substances retention; by microstructure and low-field nuclear magnetic resonance analysis revealed that the breakage of cellular tissue structure by pretreatment was the main reason for the shortening of drying time, the reduction of energy consumption and the improvement of quality; Pearson correlation analysis showed that volatiles such as aldehydes and esters were positively correlated with the a^* value, vitamin C content, and capsanthin content, whereas nonanal exhibited a negative correlation with capsaicin and dihydrocapsaicin content. This study provides theoretical and technical support for reducing the energy consumption and improving the quality of chili pepper drying.