We deeply study the automatic mooring positioning control system for sanding vessel used in the construction of three runways of Hong Kong Airport,and develop a new automatic mooring positioning control system according to its construction method,which has 50 cm dynamic positioning accuracy.Then we analyze the control model,point out the difficulties of the system,and apply the fuzzy state machine control method to overcome difficulties.The distance deviation between the center point and the start point,the distance deviation between the control point and the working line,and the angle deviation between the center line and the working line are fuzzed by the fuzzy state machine control method.The ship state is based on the position deviation and the angle deviation comprehensive results,and different control parameters are adopted in different states.According to the actual application effect of the sanding vessel,it is confirmed that the control system has higher precision and response speed.