Abstract: Due to geological hazards, the buried steel pipeline could be suspended resulted from the falling down or sweeping away of soil under it. This threatens the safety of its long-term running. Some studies are known to have been conducted on the failure problem of buried steel pipelines in partial hanging, but the formula to calculate the deflection and internal force of buried steel pipelines remains unpresented. Thusly, a mechanical model based on Winkler foundation beam is introduced to model the interaction between the pipeline and the soil. The deformation coordination of hanging and non-hanging parts is taken into account. The formula to calculate the deflection and internal force is obtained by solving differential equations describing the axes deflection of pipeline. The accuracy of the proposed method is demonstrated by a comparison with the results of Finite Element Method. It is shown that the proposed method is fairly accurate to be used in solving engineering problems.