n this research, a revised similar triangle algorithm based upon the pinhole imaging principle was proposed to establish a 3D optical measurement system with a vertical moving CCD. Although the algorithm can be applied to obtain 3D-information by using simple linear relationships, the precision of measurement can’t achieve an anticipative target. In this study, methods to correct the perpendicularity of the optical axis, enhance the resolution of capture image, and a statistics analysis method were proposed to improve measurement accuracy the measuring system. The experimental results show that the correction y the perpendicularity of the optical axis and the enhancement of capture image resolution can not improve the measurement accuracy, especially Z coordinate values of data. The statistics analysis method can be used to overcome the error due to hardware and to improve the measuring accuracy.