Mapping precision is very important for the mapping camera, and there are lots of factors that can influence the survey precision of butting mapping camera. Camera concerned here is the multi-lens butting mapping camera. The mapping precision of the camera, affected by the multi-lens area array CCD butting, the geometry calibration, the coordinate transformation and the image restores processes in the butting mapping camera of outside field of view was studied. Factors influencing the precision and the method to improve the precision of mapping camera were analyzed based on the characteristics of those factors. Through the research, the principal factors that predominate in the precision of mapping camera were decided.