Based on secondary development of ANSYS, analysis on liquefaction of embankment foundation of a reservoir is performed. Two-dimensional finite element model of representative embankment section is set up, and distribution of ratios of pore water pressure and effective stress before and after the construction of the embankment and distribution of seismic subsidence of the embankment are obtained by calculation. As demonstrated by the calculation results, ratio of pore water pressure of central part of the embankment foundation is smaller than that of both sides of the embankment foundation, and foundation treatment for eliminating liquefaction is not necessary for the central part of the dam foundation, and liquefaction degree can be effectively reduced by loading on both sides of the embankment foundation. The achievement can provide references for design of other similar projects.