High-salinity preservation is used in the salting process of traditional pickled vegetables; however, several issues exist, including environmental pollution, high energy consumption, nutrient loss, and the easy formation of pellicles. The effects of carbon dioxide (CO2) replacement at low salinity on the growth of Debaryomyces hansenii and the quality of pickled vegetables were determined in this study. Under CO2 replacement and low salinity (7%) conditions, the influence of pressure, CO2 concentration, and salt content on the growth of D. hansenii was studied. The results showed that high-pressure and high salinity affected D. hansenii growth, delaying its logarithmic growth phase. Over a six-month preservation period of pickled vegetables, the total number of colonies, acidity, and nitrite content significantly decreased, while the hardness and color of the pickled vegetables were maintained, and the pickling solution remained transparent. These results show that, at low salinity, CO2 replacement has a positive role in promoting the safe preservation of pickled vegetables, effectively controls the growth of bacteria, and provides a new way to improve the salting process of traditional pickled vegetables in China.