The coal loading design capacity of the coal port area of Huanghua Port is 178 million tons，and the wharf carrying capacity has been maintained at about 200 million tons in recent years. The capacity of the port and shipping system is very tight. It is urgent to study the factors affecting and restricting the capacity of the port and shipping system，and put forward measures to improve the capacity of the port and shipping system. To reasonably determine the capacity of the port and shipping system，this paper makes statistics，sorting and analysis on the actual operation data of the wharf and channel in the coal port area，studies the rules of ships entering and leaving the port，and rechecks the calculation by using the methods of theoretical calculation and computer simulation analysis. The results show that the capacity of the port and shipping system of the coal port area is mainly affected by the wharf，channel and their coupling and matching relationship. Under the current wharf and channel conditions，the capacity of the port area can be improved to a certain extent by improving the loading efficiency of berths，increasing berths to be berthed and optimizing ship scheduling，but the improvement degree is limited，which cannot fundamentally solve the problem of insufficient capacity of the port area. Increasing loading berths in coal port area is the fundamental way to improve the capacity of the port area.