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Gullies are well developed in Yuanmou dry-hot valley region of Southwest China, which result in intense soil erosion and severe land gradation. And local climate and soil properties are two of the main factors controlling gully erosion in this area. The frequent dry—wet alternations occurred in soil are the essential process of gully erosion. Six typical soil layers in the study area are chosen（from top to bottom are as follows: layersⅠ，Ⅱ,，Ⅲ,，Ⅳ，Ⅴ and Ⅵ） to analyze the characteristics and differences of soil erosion resistance by implementing in situ experiments of dry—wet alternation, in which soil shear strength, soil anti-scourability and soil disintegration indices are selected as the main measuring and evaluation indicators. Research results show that the values of soil shear strength of the six soil layers are apparently different, among which those of layer Ⅳ and layer Ⅴ are greater than those of other layers. With the increase of cycles of dry—wet alternation, the internal friction angle shows a fluctuating and irregular trend, while the cohesive force presents significantly negative correlation relationship in the same layer. The difference for the values of soil anti-scourability is significant among the six soil layers, and the values of layer Ⅲ and layer Ⅵ are relatively smaller than those of other layers. During the dry—wet alternation, the soil detachment rate shows a fluctuating and gradual decreasing trend and the soil anti-scourability is increased with the times of dry—wet alternations in the same layer. The average soil disintegration rates of all layers appear distinct liner correlations with the times of dry—wet alternations, among which those of layer Ⅲ and layer Ⅵ are relatively greater and layer Ⅳ and layer Ⅴ are smaller, while layerⅠand layer Ⅱ are intermediate between the former groups. Furthermore, with the feature of soft rock formations alternate with hard ones, the soil layers show an trend of firstly decreasing, and then increasing and finally decreasing for its soil erosion resistance in the vertical direction. The above results contribute to revealing gully development processes from the perspective of soil erosion.