Cavitation erosion and abrasion will bring about damage, deformation, and crack to hydroturbine blades. A portable three-coordinate measuring machine was employed to repair the defects. Infinite 2.0 six-axis portable 3-D measuring machine was used as the hardware carrier. Software ScanWorks, Geomagic Studio, Geomagic Qualify and CAD were built in the machine. Through this measuring machine, reverse engineering scanning, 3-D spatial measurement, data visualization, 3-D modelling, point-cloud data analyzing and processing, and data conversion were carried out. By comparing the original 3-D model with the defective model, location and size of the defects were obtained. The three-coordinate measuring machine is accurate, and is of guiding importance for the repair of hydroturbine blades.