In order to analyze the softening properties of the strength of soil-rock mixture under different water contents, two different types of soil-rock mixture were selected to study the strength characteristics of soil-rock mixture under different water contents by indoor direct shear test. The results show that the cohesion of soil-rock mixture generally decreases with the increase of water content under the same VBP. When the VBP is small, the internal friction angle of soil-rock mixture decreases with the increase of water contents, but the relationship between the internal friction angle and water content of soil-rock mixture becomes ambiguous when the VBP is high. The shear displacement and shear stress relationship curve of each soil-rock mixture sample is approximately hyperbolic. Under the same volumetric block proportion conditions, the shear stress of soil-rock mixture decreases with the increase of water contents. The research results provide calculation parameters for the stability evaluation of soil-rock slopes, which have practical engineering significance.