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Soil anti-scourability is one of the important parameters for evaluating the ability of soil resistance to soil erosion. In order to explore the characteristics of soil anti-scourability, dynamic change and influence factors of soil anti-scourability were studied during maize growing season by using the method of the undisturbed soil sample washing experiment and laboratory analysis. The results showed that sediment concentration decreased first and then gradually became a balanced developing state with the prolonging washing time during the maize growth season under the condition of different sloping degrees. The sediment concentration reached the highest value under the condition of 15°. With the growing of maize, soil anti-scourability and enhancement effect increased gradually and reached the maximum in the mature period. With the increase in slope, the enhancement effect of maize root on soil anti-scourability decreased gradually. Soil anti-scourability positively correlated with soil bulk density, organic matter content and >2mm water-stable aggregates significantly, but negatively correlated with ＜0.25mm water-stable aggregates. Soil anti scourability was significantly correlated with the root content, root surface area, root volume, and total root length. Therefore, it had great significance for guiding comprehensive control of soil erosion to select the maize varieties with <0.5mm root systems, and applying soil and water conservation measures to increase soil organic matter content and water-stable aggregates. The results could provide theoretical guidance to soil erosion control in purple soil areas.