Abstract: It is important to define the location of the maximal lateral displacement of soft soil foundation, which affect the dispesal of inclinometer pipe and holding the character of deformation exactly or not. Based on nonlinear finite element method, the character of lateral displacement of soft soil foundation with stage eonstruction is analyzed. It is shown that the location of the maximal lateral displacement is changeable at different eonstruction stages, which more likely lies in the vertical surface between the toe and the middle of slope of embankment. In order to get the maximal lateral displacement reasonably, it is suggested that the inclinometer pipes should be placed in the area between the toe and the middle of slope of embankment. It is also shown that the lateral displacement can not be measured eonveniently with inclinometer pipe, although which has been used in engineering widely, for there are many shortcomings within this technique. So, the technique and instrument should be improved to measure lateral displacement accurately.