The invention provides a site leveling method and system. The site leveling method comprises the following steps: a multi-spectral image of a region to be measured is obtained by positioning the region to be measured and performing data acquisition through a UAV, and radiation correction and partitioning preprocessing are carried out; acquired image data, as well as POS data and image control data are processed to obtain point cloud data; the point cloud data and design height are uploaded to a data processing terminal; and the three-dimensional plane position of a site in the region to be measured can be obtained by the data processing terminal according to the data. The invention can display an altitude difference from the plane at any position in the field in real time, high efficiency and intuition are achieved, the workload is greatly reduced and the surveying and mapping efficiency is improved.