The invention provides a buried pipeline deformation degree detection method and a buried pipeline deformation degree evaluation method and relates to the technical field of buried pipeline detection. The buried pipeline deformation degree detection method comprises the following steps: substituting detection point coordinates measured by a laser profile scanner into an elliptic equation for fitting to obtain a first fitting equation; and obtaining the difference value between the long axis and/or short axis of the first fitting equation and factory diameter of a buried pipeline to obtain a first deformation degree characteristic of the buried pipeline, wherein detection points are more than one, and the more than one detection points are distributed along the circumference of the buried pipeline, and are arranged in the same plane vertical to the axial lead of the buried pipeline. The buried pipeline deformation degree evaluation method comprises the step of carrying out evaluation on deformation degree of the buried pipeline by utilizing the deformation degree characteristics above, wherein the larger the absolute value of the difference value of the deformation degree characteristics is, the greater the deformation degree of the buried pipeline is. The two methods can truly reflect actual deformation degree of the buried pipeline; and the method allows the buried pipeline to be maintained or replaced conveniently, and can obtain safety degree of the buried pipeline more easily and accurately.