Abstract: 【Objectives】The study of evaporation in the salt lakes of the Badain Jaran Desert is of great significance for regional water resource management and ecosystem maintenance. However, existing studies face difficulties and show significant differences in results. This research aims to reveal the synergistic relationship between water surface evaporation and salinity in salt lakes, providing data and theoretical support for lake evaporation and regional water cycle research.【Methods】An in-situ evaporation experiment was conducted on the northwest side of Badanxi Lake. Different salinity water samples were prepared based on the water from Badandong and Badanxi Lakes. A Φ20 small evaporation pan was used for observations from September 2017 to August 2018, and the data were analyzed through specific data processing methods.【Results】The research results show that under the same environmental and salinity conditions, the daily evaporation amount gradually decreases from the non-freezing period to the freezing period. The monthly evaporation amount is relatively large from April to September, accounting for more than 80% of the annual total, and significantly decreases during the winter freezing period (December - February), accounting for only about 5% of the annual total. Moreover, an increase in salinity leads to a decrease in the water surface evaporation amount. Within a certain range of salinity, there is a significant negative correlation between water salinity and evaporation. In periods with low evaporation (spring, winter, and corresponding months), the relationship between them conforms to a linear model, while in periods with high evaporation (summer, autumn, and corresponding months), it conforms to an exponential model. The annual evaporation amount conforms to the exponential model (y = 3436.2e−0.097x). Even when the salinity reaches the maximum value of 441.5 g/L in the study area, water surface evaporation still occurs. In addition, by introducing the conversion coefficient of high-salinity water surface evaporation, it was found that there is a critical value for the influence of salinity on evaporation. When the salinity is higher than this critical value, the higher the salinity, the lower the evaporation amount.【Conclusions】There are seasonal variation patterns in the evaporation amount of salt lakes in the Badain Jaran Desert. Within a certain range of salinity, it has a negative correlation with salinity and conforms to different models in different periods. There is a critical value for the influence of salinity on evaporation. The research results can provide an important basis for regional water resource management and ecological protection.