The invention discloses a point cloud based 3D reconstruction method for an operation scene of a distribution line. Operations including conditional filtering, de-sampling, outlier removing and segmenting are carried out on an initial point cloud to obtain point cloud of to-be-constructed parts, as a lightening arrester and a cross arm, of the distribution line, a SIFT 3D algorithm is used to extract key points, FPFH characteristics are used to construct describing vectors of the key points, coarse registering and improved ICP fine registering are used to complete registering of the point cloud, a complete 3D point cloud of the parts is obtained, an offline model library is established, the point cloud is collected in real time, the point cloud of the parts is registered with models of themodel library, 3D reconstruction is completed, curved surfaces are reconstructed via a Poisson surface reconstruction method, and a 3D model is obtained. According to the invention, semi-autonomous 3D reconstruction of the distribution line scene is realized, manual intervention is reduced, aimed registering serves as an important step of 3D reconstruction, SIFT 3D key point extraction and FPFH characteristic describing vectors are used, the quality of the key points is ensured, point pair relation is provided with weights, incorrect point pairs are eliminated, the registering speed is improved, and the 3D reconstruction efficiency is improved.