A precise measurement method for three-dimensional coordinate of points’ larger than ten meters in field working space is presented. And the problem that the mosaic precision of cell measuring data is very low in large three-dimensional free-form measurement is solved simultaneously. Measuring pictures of visual characters called global control points at determined points are taken by special metrical camera. After processing the pictures using high precision image processing technique, automatic matching technique of global control points and ray bundle adjustment technique, the three-dimensional coordinates of global control points are retrieved. Experimental results show that the method can attain relative accuracy about 0.073% by using common digital camera and can be accomplished flexibly, freely, rapidly and accurately.