Earthwork volume caculation refers to the engineering volume of excavation, landfill, transportation, stacking, and other operations of earth and rock in construction, road, water conservancy, mining, and other projects. The size of the earthwork is directly related to the investment and progress of the project. Therefore, accurate calculation of earthwork has become an important link in engineering design and construction. There are many traditional earthwork calculation methods, including cross-section method, grid method, contour line method, etc., but these methods require manual measurement and drawing, which is time-consuming and labor-intensive, and are prone to errors and omissions. With the advancement of science and technology, the use of lidar scanning and processing technology for 3D reconstruction and analysis provides a more efficient and economical technical path for earthwork calculation.