Abstract: Pingding-Huama fault in southern Gansu Province is an active fault at present with characteristics of sinistral strike-slip. Suoertou landslide is a typical creep fracture zone landslide developed along Pingding-Huama fault zone. Field investigation and monitoring data reveal that Suoertou landslide is a giant landslide characterized by the development of many secondary landslides; landslide is composed of fault fracture zone, gravel soil and accumulated loess; the deformation of the landslide is intense; the landslide has many tension fractures and shear fractures lying in the creep deformation state. Suoertou landslide is formed under the coupling of endogenic and exogenic geological processes: the active fault controls the formation and development of the landslide, the rainfall is the main factor triggering the revival of the landslide. Therefore, the further study of the formation mechanism of Suoertou landslide can provide theoretical basis for the prediction and control of the creep fracture zone landslide.