Abstract: A global control Fuzzy Genetic Algorithm (FGA)was applied to the structure optimization.The method given here differs from the standard GA methods (SGA) in taking the whole process of Genetic Algorithm selection,crossover,mutation and the change of searching space into global fuzzy control.The quality of FGA method is verified using two typical mathematical multi-peak functions.The results of simulation show that this kind of fuzzy genetic algorithms can efficiently avoid being entrapped into local optimum and obtain a higher efficiency of optimizing process.A rivet structure,which contains integer and discrete variables,was optimized with FGA method.It shows that a better connecting efficiency with less converging steps can be obtained.