Abstract:[Objective] The effects of oil pollution on soil water holding capacity and water supply intensity were studied in order to provide a theoretical basis for the study of organic pollutants migration and transformation in soil.[Methods] The main soil type (loessial soil) in the oil-producing area of northern Shaanxi was used as the test material, and five different levels of polluted soil (0, 0.5%, 1%, 2%, and 4%) were obtained by artificial simulation. The soil water retention curve obtained for each treated sample was analyzed using the van Genuchten model, to investigate the difference of soil water-holding capacity, water availability and specific water capacity among different treatments.[Results] The water-holding capacity of soil was significantly reduced by oil pollution, and the greater the pollution concentration was, the lower the water-holding capacity was. Oil pollution had a significant influence on the soil water characteristic curve in the low suction section of pF1.5 and the high suction section above pF3.5, and its influence on soil structure was more significant. The high concentration of oil pollution caused the decrease of soil water availability, exacerbated soil desiccation, which was not conducive to the coordination of the contradiction between the arid climate and the water demand of plants. With the increase of oil pollution concentration, the soil specific water capacity also showed a significant decreasing trend, and the suction range corresponding to soil available water was narrowed.[Conclusion] Oil pollution has significantly reduced the soil water-holding capacity and water supply intensity, exacerbated soil drought and brought serious harm to plant production and ecological environment.