Abstract: Simplifying the pipeline inside a landslide body to a large bending deflection beam and taking the pipeline outside landslide body a beam with half unlimited-length or pole, thinking of the pipe beam's geometric nonlinearity, physical nonlinearity of soil's vertical resisting force outside the landslide body and the action of pipeline's inner pressure and temperature difference, based on the continuity of pipeline's inner force and distortion both inside and outside the landslide body, derived a relative calculation on pipeline's inner force and displacement under both conditions that equivalent axial force means a tension or a pressure and puts forward a discriminant when equivalent axial force is a tension or a pressure. Displacement and inner force calculations on buried pipeline in vertical landslide will finalize resolutions of two nonlinearity e-quations and these can be solved by means of Newton iteration method or plotting method. The article also provides calculating example and result analysis, and discusses shortcomings in previous theory.