Abstract: This paper introduces a capacity measurement method for large vertical tanks based on 3D laser scanner. The point cloud data of the vertical tank surface are collected by the 3D laser scanner and the 3D model of the tank body is reconstructed to calculate the tank volume and build volume table. Calculation model for vertical tank volume based on point cloud analysis and the application of observation method, median filter and Leit criterion (3 σ criterion) in the pretreatment of point cloud data are discussed, and related formulas using least square method, accelerated iterative method and equivalent area method to calculate radius of tank plate are given in this paper. HDS7000 3D laser scanner was used to conduct an experimental test on a vertical tank with the volume of 2×10⁴ m³, and the repeatability and reproducibility of the 3D laser scanner and related methods in volume measurement were checked. The results show that the biggest deviation of the tank plate's radius measured by 3D laser scanner method and total station instrument method required by verification regulation of capacity measurement of vertical metal tanks is only 0.1 mm, and the relative deviation of volume is less than 1‰, which meets the requirements of verification regulation.