The optical phase-conjugate resonator consists of one normal mirror and one phase-conjugate mirror made of an instantaneous response lossless Kerr medium. Using the nonlinear feedback, we control the temporal chaos in the phase-conjugate resonator and spatiotemporal chaos in the coupled phase-conjugate map system. Stable control has been realized. The simulation shows that this controlling technique can be implemented easily in practical systems just by adjusting the feedback strength. The in-advance knowledge of the dynamic system is not required. The results are useful to theoretical analysis of chaos in phase-conjugate resonators.