This paper investigates the stabilization and H-infinity control of nonlinear port-controlled Hamiltonian (PCH) systems subject to actuator saturation and proposes a number of new results First the stabilization problem is studied and a control design method is developed by using both the dissipative Hamiltonian structural and saturating actuator properties Second for the case that there are external disturbances in the systems an H-infinity controller is designed to attenuate the disturbances Finally the results obtained for Hamiltonian systems are applied to the stabilization and H-infinity control of nonlinear affine systems subject to actuator saturation and several interesting results are presented Study of an example of power system with simulations shows that the controller proposed in this paper is effective (C) 2010 Elsevier Ltd All rights reserved