The large-scale interlayer soil in heavy saline-alkali land formed by concentrated and continuous sections after the water-saving construction with large-scale and high efficiency in the Weigan River irrigation area was used to solve the practical problems of large quantity of engineering and high cost of production in the existing improvement measures for heavy saline-alkali land.The changes of water and salt in soil under winter irrigation conditions with different improvement measures were studied through field plot experiment.The results showed that the deep-turning treatment had the highest desalination rate of 75.9% among all the treatments， followed by ditching， drilling and sand filling， and drilling and sand filling treatment， accounting for 51.5% and 39.4%， respectively.The desalination rate of ditching and drilling was relatively close， accounting for 38.2% and 37.4% respectively.The lowest desalination rate of ditching was 33.9%.The content of salt under each measure in the 0-20 cm soil layer after two and three times of winter irrigation decreased from 7.06-11.61 g/kg before winter irrigation in 2020 to 2.00-5.91 g/kg after winter irrigation in 2022， with a desalination rate ranged from 76.8% to 382.5%.It is indicated that the surface soil has been improved from the initial medium-heavy saline-alkali soil to light-medium saline-alkali soil， reflecting the retarding effect of clay interlayers on the transport of water and salt.Drilling and sand filling can be used as a simple and practical measure to improve the effect of salt leaching and suppress the return of salt in saline-alkali land.It will provide basic data and technical reference for the rational selection of improvement measures for interlayer soil in the heavy saline-alkali land.