A fill-form mixing material molding method for flow passage of turbomachinery such as hydrodynamic torque converter in the process of non-contact measurement was proposed, and the passage structure was extracted by two different materials of silicone rubber and ultra-lightweight paper clay, where silicone rubber got accurate shape of passage and paper clay supported the silicone rubber. Compared with traditional molding method with sole silicone rubber, this method overcame the shortcoming of large modeling deviation caused by deforming of silicone rubber after it was taken from flow passage but could not rebound to original shape, and the data of mapping point cloud of passage pieced by ICP algorithm coincided well with the known blade. The average deviation decreased steeply from 300.7 μm of the sole silicone rubber molding method to 28.5 μm of the mixing material molding method, and more accurate extraction and reconstruction of special flow passage was accomplished which provids a more effective reverse engineering method to measure and check the deviation in design and manufacture.