A simulation model for an open-ended cyclic queuing network system is established to test the operating performance of the fleet. The simulation-optimization method for stochastic discrete event system is raised on the basis of statistical hypothesis testing to select the optimal fleet. 建立了海运船队营运的开式循环排队网络模拟模型,并运用随机离散事件系统的模拟优化方法选取了最佳船队。