The invention relates to a digital image forming technique for an anchor rod tray load. The digital image forming technique is performed as follows: carrying out pretreatment of an anchor rod tray; arranging a light source and erecting a camera; establishing a coordinate system; calibrating a stereoscopic photography system; carrying out searching and processing; carrying out reference coordinate determination before deformation; carrying out reference coordinate determination after deformation; calculating a strain value; and calculating a load. A high-resolution digital single lens reflex camera is used for shooting to obtain images before and after deformation of the anchor rod tray; with a related searching method, identification is carried out to obtain a same point; comparison of changes of the coordinates is carried out to obtain the strain of the point; and coordinate changes of all marking points are identified to obtain a strain field of the anchor rod tray; a stress field is obtained by combining the bending rigidity of the anchor rod tray; and back integral calculation of the stress field is carried to obtain a real-time load of the anchor rod.