Aiming at the difference of exposure degree of laser fringe image in 3D measurement of complex reflectivity objects,an adaptive multi exposure method is proposed to obtain 3D point cloud.According to the imaging principle of the developed acquisition system,the imaging function of the vision sensor is fitted.The abrupt change point of reflectivity in the geometric center of the initial fringe is set as the reference point,and the fringe information on the complex reflectivity object is collected by segments according to the reference point；then,the adaptive exposure parameters are calculated according to the average reflectivity of each segmented area；and the collected laser stripe information is fused according to the reference point.Stepping motion is adopted in the measuring platform to realize the whole scanning of objects.The center coordinates of fringes are extracted by quadratic fitting barycenter method to generate 3D point cloud information.The experimental results show that the adaptive exposure accuracy is higher than 90%,the fringe energy concentration is greater than 5,and the root mean square error of 3D point cloud is less than 0.3mm.It is demonstrated that the proposed method effectively solves the problem of over exposure or under exposure of fringe image,which can realize 3D measurement of complex reflectance object in dynamic state.