Abstract: The inland waterway service area (IWSA) is an important auxiliary navigation facility along the inland waterway, which provides special services including berthing and replenishing of daily necessities for vessels and mariners during their voyages. The water area and maximum number of vessels that can be accommodated simultaneously are vital for the planning and designing of the IWSA, which is associated with the category of service, passing vessel flow rate, demand probability (driving-in rate) and service duration (turnover rate).Taking into account the randomness of the dynamic traffic system and the service duration, a simulation model using AnyLogic^® for estimating the water area of the IWSA based on the characteristics of the inland vessel traffic and service functions is established in this paper. On the basis of the field data concerning three service areas on three different inland waterways in the Yangtze River delta, the water area of the service areas is simulated and analyzed. The simulated results show that the number of berthing vessels and water areas of the service areas predicted by the simulation model are in good agreement with the actual situation, compared to the empirical formulas. The sensitivity analysis is adopted to identify the impacts of different distributions and expected values of the driving-in rate and turnover rate in the water area of the IWSA. According to the simulation and regression analysis, the water area can be simplified to a continuous function of the flow rate and averaged tonnage of vessels on the corresponding inland waterway, which can be used conveniently and reasonablely to estimate the water area needed for the inland waterway service area.