Based on the optical detection technology, the columnar machine parts are tested by laser scan? ning and three-dimension (3D) reconfigurable system is designed. Traditional measurement methods lead to a small deformation of the measured object surface, and even the accuracy decreases. This problem is solved with realization of a non-contact measurement by the introduction of optical technology. Laser is used widely due to its high speed, high precision, large range and strong anti-electrooptical jamming. The outer diameter and the height of columnar mechanical parts are measured precisely, and the surface of the 3D reconstruction is achieved. The system is feasible and simple, it can restore precisely the location of the object, geometric shapes, and 3 D in? formation that the 2D image detection method cannot provide.