Abstract: In this paper, usingparametic variational principle the elastoplastic analysis and contact analysis and analysis method for block-seams Model is established to simulate the nonlnear behavior(e. g.failure, sliding and contacting) of rock and soil structure such as slope and foundation.The elastoplastic analysis and contact analysis of rock and soil structure are deduced to find the minimum of functional with the constraint of yield and contact conditions so that only a linear complementary problem is to be finally solved.Thus the elastoplastic analysisand contact analysis all contact analysis of rock and soil structures are treated in the same way.Turthrmore,the non-associate flow and strain softening problem can be solved easily by this method,the iterations, which are essential in the traditional elastoplastic analyis and contact analaysis method,are avoided and the computational effort is significantly reduced.