In order to describe the effects of interference cancellation performance on the simultaneous jamming and intercepting system quantitatively, the concept of jamming-intercepting outage probability with imperfect interference cancellation was proposed, the closed-form expression for jamming-intercepting outage probability was derived and the asymptotical expression was further obtained for ideal interference cancellation. Based on the derived performance closed-form expression, the optimal jamming power that minimizes the jamming-intercepting outage probability was identified. Accuracy of the analytical results and the correctness of optimal jamming power were justified through Monte-Carlo simulations. The results demonstrate that the jamming-intercepting outage probability decreases as the interference cancellation rate increases, decreases first and then increases as the jamming power and the transmit power increases, and the optimal jamming power increases as the transmit power increases, while the optimal jamming-intercepting outage probability converges to constant as the transmit power increases.