Numerical simulation method is a powerful technique for chaos analysis. The traditional analytic method can't predict the behavior of the piecewise linear system (PLS) exactly because of the non-smoothness of the system, if the system is strong nonlinearity. The piecewise linear vibration isolation system with single degree of freedom (SDOF) was studied in this paper. The “inverse” integral method was used to determine the crisis time (piecewise time) of the system and then an advanced Runge-Kutta integral method was applied to simulate the system. It was found that there exists complex dynamical behavior including chaotic motion. The parameter region when the bifurcation and chaotic motion occur was determined using numerical simulation.