In order to satisfy the positioning accuracy of deep cement mixing vessel that is developed the first time in China,we propose a new automatic mooring positioning system with full consideration of operation conditions and working efficiency,and combine the fuzzy control thought and state machine to apply to the mooring positioning system.The fuzzy control can fuzzy on the current state of vessel.The state machine can divide the mooring positioning process into several states,different control parameters with different status to ensure fast and accurate positioning of vessel.The results show that the system satisfies the needs of the project,improves the construction efficiency and achieves good results.