Abstract: Using the self-made shear instrument, the shear resistant intensity of the mixed material by the coal gangue and waste soil was measured. And the effect of rainfall intensity on the mixed material stability was also studied by artificial rainfall experiments. The results showed that when the proportion of coal gangue in the mixed material was in the range of 30% and 70%, the shearing strength increased with the coal gangue proportion increasing. When the proportion of coal gangue was more than 70% or less than 30%, the shearing strength was not related to the proportion of coal gangue. In the mixed material, the soil moisture was negatively related to the shear strength. The rainfall would reduce the shear strength of the mixed material, and then reduce the stability of slope. In the aspect of slope stability and plant growth, the suitable proportion of coal gangue and waste soil was about 50%.