Rapid reverse technology is one of the key technologies with which the enterprises develop new product and occupy the market rapidly. How to realize the reverse measurement and CAD geometry reconstruction rapidly and accurately is always the most important focus for the researchers. Based on the laser scanning technology, the realization principle of the laser line scanning measuring system is presented and the approaches to improve the precision are also analysed in the paper. The self-adaptation adjustment of the probe position can move the light knife image to the optimal imaging area of the CCD according to the calibration result, which will ensure the measurement precision of the CCD image. With the inner velocity loop and outer position loop feedback control, the simple axis position precision of the mechanical system can be controlled within 5um. In order to pick up the points of the light knife centre rationally and exactly, the reconstruction-disperse iteration algorithm is put forward. After processed by different iteration times, the optimal points can be obtained. The reconstruction method of curve and surface based on NURBS is also given. The paper presents the application and realization of the system at last, which realizes the curve and surface measurement with high precision.