In this paper, an innovative image-technique-based fast industrial-robot positioning system for assembly implementation is presented. Two laser projectors, that is, a laser pointer and a line laser, and an image sensor are used to construct the innovative system to scan and obtain a 3D point cloud model of the object to be assembled. The system is then integrated with a 6-axis industrial robot to define the insertion position in a semi-autonomous manner. This system can save up to 80% of the manual teaching time for defining robot insertion positions by using a teach pendant. The whole system has been tested on four insertion tasks that require high precision. The results of experiments confirm the effectiveness and efficiency of the system for high-precision tasks. This innovative system can be used in many industrial-robot-based automated assembly tasks.