The invention discloses a control system for assisting a ship to enter and exit a port by utilizing DP. The system comprises a measure part, a control part, a power part and a thruster part, the control part comprises a controller, a manual control unit, an automatic control unit and a computer software system, wherein the manual control unit and the automatic control unit are connected with the controller and used for driving a ship to sail, a laser positioning system which is connected with the control part through a wireless signal and used for monitoring the gradually close distance of the ship in real time is arranged on a port or a wharf, when the actual ship position parameter reaches a preset distance parameter for automatically controlling shifting of the ship, a signal for driving the ship to automatically shift is sent to the automatic control unit, and meanwhile, a signal for stopping manual control is sent to the manual control unit, so that the ship is controlled to automatically and stably stop to a preset stopping point. According to the system, accurate control on a main propeller and a side propeller can be realized through real-time signal feedback, and the accuracy of the final stopping position of the ship is realized.