Abstract: The shear strength reduction finite element method has become a main technique in the field of slope stability analysis due to its advantages of dealing with complex geometry and nonlinear material, and no need of predefined critical slip surface. Three main problems of shear strength reduction technology including the criteria for failure are discussed. An example analyzed by the ideal elastoplasticity model and rheological model is used to show the advantages and disadvantages of rheological model applied in slope stability calculation. And a user-defined subroutine is developed based on the Duncan-Chang EB model, Mohr-Coulomb model and logarithmical shear strength model, which is used to find the safety factor of Nuozhadu Embankment Dam with a height of 261.5 m.