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An experiment with two factors randomized block experimental design was conducted based on the evaporation of standard 20 cm pan to study the effect of different irrigation scheduling on salt distribution and salinity leaching in soil profile of cotton field with drip irrigation under plastic mulch. The results showed that to increase irrigation frequency and water amount was beneficial to soil salinity leaching in horizontal direction. The actual depths of soil salinity leaching for 5 d and 8 d frequency treatments were 0 to 20 cm and 0 to 30 cm respectively. As the soil depth increased, the soil salinity content for 5 d frequency treatment showed a first rising and then decreasing trend, while for the 8 d frequency treatment, it kept an approximately constant value in 0 to 100 cm soil profile. The soil salt content in 0 to 60 cm soil depth for medium water amount treatment (T60) was lower than that of high (T80) or low (T40) treatment. Compared with the soil salt content before sowing, the salt content in 0 to 20 cm soil layer at harvest time increased and decreased in 30 to 60 cm soil layer. The salt content within 0 to 60 cm soil layer showed an increasing trend as a whole. The salt content of medium water amount treatment (T60)showed a minimum variation, and the desalting rate was 0.44%. The irrigation scheduling had no significant effects on soil salt content in 0 to 100 cm soil layer. In addition, with the same irrigation frequency, applying high or low water amount was not beneficial to boll weight and yield improvement however. Combining high irrigation frequency（5 d） with medium water amount （T60） treatment acquired the highest seed cotton yield by9.18t/hm2, and it was regarded as the optimal irrigation scheduling for reasonable soil salt distribution, good salt leaching effect, higher yield and effective water application. 