A complete theoretical model for slope destabilizing mutation has been set up by studying the geomechanical model and the influences of all circumstantial factors on slope stability,and by applying nonlinear theory.This paper analyzed the influence of controlled variables in the mutation model on the slope in causing slow or fast creeping.As the limit equilibrium stability analysis method of rigid bodies has some defects in slope stability assessment,the new theory of rigidity destabilization is helpful in forming criteria for judging slope creep destabilization.This analysis explains well the underlying causes of creeping slope destabilization and proves the feasibility of studying slope creep with a mutation model.