The current-mode controlled switched-inductor Buck-Boost converter operating in discontinuous conduction mode was chosen as the research object. Firstly, according to its the discrete mapping model, the nonlinear dynamic behaviors of circuit system were analyzed by Matlab numerical simulation. Secondly, the resonant parametric perturbation method was applied to control the chaos in circuit system. The suitable parameters of perturbation amplitude and perturbation phase angle were calculated by theoretical analysis and numerical simulation. Finally, the corresponding Matlab/Simulink simulation and experimental circuit validation were done. The experimental results were comparable with simulation results. The result showed that the chaos of the circuit system could be reduced efficiently by resonant the parametric perturbation method.