The microstructure and material composition of the soil in the shear zone of the Moli Village landslide in Guoye Town, Zhouqu County were studied using a stereomicroscope, X-ray diffraction (XRD), and scanning electron microscope (SEM). Obtain linear, arc-shaped, and disordered scratches on the shear surface after soil shear failure in landslide shear zones under different vertical pressures. The material combination of landslide shear zone soil is mainly composed of quartz, chlorite, calcite, and muscovite. And explained the influence of various mineral compositions on landslide stability. Observation of landslide shear zone soil clay minerals with directional arrangement and obvious micro pores and micro cracks using scanning electron microscopy at different magnifications. These micropores increase the porosity of the soil in the landslide shear zone, Once the slope structure is damaged due to shearing. Due to the action of rainfall or groundwater, huge pore water pressure can be formed, leading to landslide disasters. Based on the changes in microstructure and material composition, the frequency, stage, and formation mechanism of landslide activity can be analyzed. This research provides a basis for landslide control and stability evaluation.