The principle of determining 3D coordinates of a point in the space using multi-joints 3D scanner is described. The error metric between the real value and the designed value of structural parameters of multi-joints 3D scanner is analyzed. It is pointed out that the calibration problem is measuring error minimization problem over all possible values of the parameters, and a genetics-based calibration algorithm for the structural parameters of multi-joints 3D scanner is presented. The experiments show that the proposed method is effective to calibration.