Micro steel pipe piles are increasingly widely used in fields such as landslides and foundation pits. Some practical method and theory for calculation on micro steel pipe piles are proposed but not yet formed a unified cognition. The number of pile rows and internal force and embedded depth are calculated by the shear resistance along the sliding surface through the design calculation theory and the appropriate pile diameter and steel pipe wall thickness are selected; calculation of characteristic values of horizontal bearing capacity of piles is checked, eventually completed design work. The existing calculation theory does not consider the shear strength of pipe body which is conservative. In this design, the shear strength of the matter body is taken into account, and the design is optimized and the engineering quantity is reduced. It is proposed to use displacement controlled horizontal bearing capacity characteristic values for verification. By long-term monitoring of pile top displacement, the steel pipe pile support design has achieved the goal of preventing sliding and the landslide was in stable state after treating.