Abstract: 【Objective】 To explore the law of water and salt movement in different salinized soil conditions in cotton seedling stage, and clarify the relationship between the seedling formation law of different cotton varieties and soil salinity,the results can provide a theoretical basis for cotton cultivation under salinization conditions. 【Methods】 The main cotton varieties in southern Xinjiang Tahe 2, Xinluzhong 56, and Xinluzhong 87 were taken as the research object, a completely randomized pot experiment was arranged in 2021. Three salt gradients shall be set according to the national soil salinization classification standard: 3, 5 and 15 g/kg (designated as S₁, S₂ and S₃ in turn), and the test soil was the original saline soil in Xiaohaizi irrigation area in southern Xinjiang. 【Results】 (1) After a period of irrigation, under the condition of the soil salt content of 15 g/kg, the soil moisture content was higher than that of other treatments; (2) The salt content of 0-20 cm soil layer with different salinity treatment was significantly higher than that of 20-40 cm soil layer. With the increase of the initial salt content of the soil, the salt return to the surface layer increased; (3) According to the fitting equation, when the soil salt content of Tahe 2, Xinluzhong 56, and Xinluzhong 87 cotton reached 6.94, 7.04 and 7.09 g/kg, respectively, the number of adult seedlings was 0, which can be used as the salt resistance limit value of cotton in the seedling period. 【Conclusion】 When the soil salt reaches the salt resistance limit value, soil permeability is weakened, salt aggravation seriously affects the cotton seedlings. It can be seen that the cotton seedling period responds significantly to the soil salinity, and the cotton planted in saline soil should be controlled by salt water, and soil salt content should be adjusted in time.