To analyze the traffic performance of partial constricted section in inland waterway,we design a simulation model according to the channel characteristics of single-line alternating navigation and analyze the traffic performance and capacity of constricted section under different conditions.The results indicate that the size and directional distribution of vessel traffic flow affect the traffic performance:centralized dispatching of vessels when the difference of traffic flow between two directions is large，is beneficial to the improvement of the traffic efficiency，but will increase the delay of some vessels;the traffic capacity decreases with the increase of the length of the constricted section,and approximates a minimum value when the length increases to a certain value.In practice,traffic organization and waterway regulation schemes can be arranged reasonably according to shipping demands.