Aiming at the economic benefits of various schemes for the channel deepening project in the south passage of the Yangtze estuary，we adopt a double clock mechanism to optimize the model of ship pre-queuing model to establish a marine traffic simulation system.Based on some factors including characteristics of channel,ship sailing,ship dimension,tide and navigation regulations,we solve the queuing problem in the channel by the simulation comparison,and obtain parameters for the evaluation and estimation of economic effects of the South Passage channel deepening project,such as queuing time and utilization ratio.Consequently,it can offer reasonable suggestions for scheme choosing for the channel deepening project.