Simulation is a powerful tool for analyzing and designing of industrial and service systems. But simulation can’t optimize the system elements and needs additional methods for optimization. In this study a multi- objective simulation optimization is dealt with. To determine the optimum factor levels, grey-based Taguchi approach is used. Since Taguchi method is designed for single objective problems, grey relational analysis is combined with Taguchi method to solve this multi-objective simulation optimization problem. Additionally, in the stage of grade relational calculation of grey relational analysis (GRA) fuzzy AHP weighting process is adopted to determine the weights of grey relational coefficients.