The invention discloses a high-speed and high-precision tank volume measurement method and device based on three-dimensional laser scanning. The method comprises the steps of making an experimental scheme and controlling the data collection quality; collecting and acquiring three-dimensional point cloud data of the outer surface of a tank through a three-dimensional laser scanning platform; carrying out spatial three-dimensional modeling and establishing a three-dimensional model of the tank through the acquired three-dimensional point cloud data of the outer surface of the tank; analyzing the three-dimensional model of the tank and calculating the volume of the tank through the section method. According to the method, the volume of tanks such as tank trucks, storage tanks and tank containers can be quickly and accurately measured, operation is simple, the safety is high, the labor intensity is low, the data processing time is greatly shortened, influence of materials of the tanks and the like is reduced, and data calculation is convenient. The method can adapt to different work environments and is particularly suitable for the quality supervision department to calibrate and retest the volume of the tanks quickly.