The invention discloses an automatic navigation path tracking method for an aquaculture workboat. The method comprises the following steps: 1, collecting the position information of corners reflecting the contour of a work region, and obtaining the target navigation lien and speed of the workboat through track planning; 2, collecting the real-time position, navigation and speed of the workboat, setting the navigation speed of the workboat, and judging whether a target path needs to be switched or not; 3, calculating a tracking target point of the workboat through employing a method of real-time point insertion; 4, enabling the attitude and movement state data of the workboat to be compared with a tracking target point and a target path, obtaining the navigation direction and speed deviation, obtaining the navigation direction and speed control amount through employing the PD and PI algorithms, and finally obtaining the control amounts of left and right paddle wheels; 5, carrying out the real-time navigation control of the workboat according to the final control amounts. The method can remarkably improve the effect of automatic navigation path tracking, and provides guarantee for the high-efficiency completion of aquatic plant cleaning and uniform bait casting.