Abstract: In a wastewater treatment plant, there are some problems that the impellers of submersible mixers were damaged with abrasion and the impellers' spare parts must be imported. For solving the problems, a new impeller was designed by reverse engineering. The authors acquired these separated point clouds of the impeller by a coordinate measuring machine. These point clouds were treated and obtained a combined point cloud, and the impeller surfaces were remodeled with the Surfacer software. Then the Pro/E software was used to develop the impeller solid model. The impeller solid model obtained by the reverse engineering was successful in mould making, impeller manufacturing and impeller anti-abrasive researching.