The goal of preliminary mobile laser scanning (MLS) data processing is generating a unified point cloud in a required coordinate system. During this processing calibration of 2D scanners and digital cameras, point cloud adjustment, data filtering such as removal of noise and remirror points. Currently huge amount of software is developed for solving these tasks, but a degree of their auto-mation differs. Depending on software, type of scanned area preliminary MLS data processing technique can differ. The analysis of carried out scanning results with the task of revealing their pe-culiarities, determination of the preliminary data processing order and deciding about necessity to accept additional manual procedures.