A fuzzy governor power system stabilizer (FGPSS) is designed for a hydro-generator unit based on fuzzy control theory and its parameters are optimized using Genetic Algorithm (GA) to overcome the subjectivity in design of controller. In order to raise search speed and accuracy, the conventional single-point crossover GA is improved and a new GA named Head-and-Tail Alternate Crossover GA is proposed. The head-crossover and tail-crossover is used alternately in the algo- rithm, which ensures that optimized probability of every parameter is approximately equal. The parameters of FGPSS are optimized using the algorithm and the result indicates that the algorithm is more quickly and precisely than Error-and-Trial method and conventional GA.