Image measuring instrument has been widely used in the field of industrial measurement, especially in the measurement of precision planar parts. When measuring a full set of parts, the traditional image measuring instrument needs to manually control the platform movement to reach the measuring position, which leads to prolonged measurement time and low efficiency. In this paper, a universal image measurement instrument is used as the experimental platform. The feature is moved from any position of the platform to a small field of vision through a large field of vision in the way of continuous use of the camera of large and small field of vision, which is corrected by using the small field of vision to achieve precise positioning and optimize the measurement time. The experimental results show that this method can effectively move any feature point within the range of large field of vision to the center of small field of image. Finally, an automatic positioning method for thin sheet parts of the image measuring instrument is proposed. The experiment proves that this method can effectively reduce the measurement time and the movement error of feature points is within 0.05mm.