This paper describes a well-designed and calibrated simulation model to solve the design of Ships' routeing system which provide useful insights about complex maritime transportation routes. Real data from shanghai port Vessel Traffic Services Center (VTS) are used as input for evaluating four traffic policies. The simulation model mainly focuses on the transit traffic in the channel. This study provides a platform to analyze the effects of factors such as Rules and Regulations, number of tugboats and pilots, vessel type, traffic density and meteorological conditions on the maritime traffic in the channels. The model provides quantitative information and helps administrators in decision making to achieve desired safety level and improve the efficiency of vessel traffic in ports and waterways in shanghai.