This research was aimed to improve an inspector’s performance on the training through 3D model by motivation technique. The subjects were divided into 3 groups; the control, the feedback training, and feedback training with reward groups. The subjects participated in the last group would get rewards or punishments such as money given or deducted during the test with 3D model software with Thai characters and Roman characters representing defects and backgrounds. According to the experiment, the performance in terms of speed and accuracy in detecting defects in training with reward group increased. In other words, feedback with motivation training could make visual inspectors spend less time detecting defects to their minimum because motivation attracted them in the experiment. Therefore, the time spent seeking defects in this group decreased. The performance of training with reward group is higher than other groups which showed the statistical significance at the .01 level.