A present invention relates to a novel hybrid intelligent control system and method for power generating apparatuses, in which the control system comprises: a fuzzy sliding mode speed controller, embedded with a fuzzy inference mechanism so as to be used for controlling the speed of a power generating apparatus; and a radial basis function network (RBFN) pitch controller, being embedded with an on-line training RBFN so as to be used for controlling the pitch angle of a turbine coupled to the power generating apparatus. In a variable-speed energy conversion system using the aforesaid control system, the turbine can be driven to operate at its maximum efficiency by adjusting its blade pitch angle in response to the variation of the input flowing into the turbine, while allowing the shaft speed of the power generating apparatus to be controlled by a fuzzy interference mechanism so as to achieve its maximum power output.