The invention discloses a free curved surface product reverse engineering modeling prototyping method based on three-dimensional optical scanning. The free curved surface product reverse engineering modeling prototyping method based on three-dimensional optical scanning includes over-scanning, reverse modeling, quality analysis, rapid prototyping, and printing of the final three-dimensional model,and is characterized by pasting mark points on the front and back surfaces of a free curved surface product and setting a rotating disk at the same time, realizing integrity and accuracy of scanningby means of auxiliary paste points on the rotating disk, utilizing a non-contact three-dimensional optical scanner to easily scan the full view of a multi-curved-surface product at higher speed, afterreverse modeling, utilizing Geomagic Qualify software to perform 3D comparison of the sampling point on the obtained reverse model and the point cloud data in the step (2), and according to the analysis and comparison situation, continuously correcting and scanning the point cloud data or the reverse three-dimensional model, so that the free curved surface product reverse engineering modeling prototyping method based on three-dimensional optical scanning has the advantages of guaranteeing the quality of the output product, improving the work efficiency, being low in the product quality reworkrate and saving printing of consumables.