Marine diesel-generator speed-frequency control system based on sliding mode control (SMC) scheme is introduced in this paper, which is capable of providing good and consistent speed-frequency control performance, despite wide variations in the system operating conditions. The SMC scheme consists of a conventional governor based on a standard speed error signal, and an auxiliary loop incorporating current signal as a feed forward control. The former loop serves to provide the speed regulating requirements while the latter serves to compensate for the influence of generator load current on dynamic behavior.