Changzhou complex and lock have promoted effectively the transport capacity of the Xijiang waterway. However, with the increase of traffic, the existing navigation lock facilities can not meet the traffic demand. In order to ease the congestion and delay of the navigation locks, we analyzed the lock’s traffic in recent years, and forecast its capacities from 2010 to 2015 based on a new analytical model for the average lockage tonnage. Some suggestions were put forward to improve the existing lock’s capacity, including the lock management mode, standardization and enlargement of vessels, lock scheduling, engineering measurement, etc.