Disclosed is a system for shape error in-situ measurement of large-scale torus, which comprises an attitude adjusting part, a rotating part and a measuring part. The attitude adjusting part comprises an attitude adjusting platform, an attitude adjusting platform motor and an adapter panel, wherein the attitude adjusting platform can adjust the rotation angles along z-axis and x-axis, the angle adjusted is controlled by the attitude adjusting platform motor, and the attitude adjusting part is connected with the rotating part through the adapter panel; the rotating part comprises a rotating index plate base and a high-precision rotating index plate which is released from fixation by a lever for rotating, rotated manually for a required angle, and then fixed again by restoring the lever; the measuring part comprises a sensor clamp, sensor holders, contact sensors and associated equipment, wherein the sensor clamp is positioned with the rotating index plate by a mandrel and then fixed by two bolts and nuts; and the sensor clamp has four groups of sensor jacks in total, with at least three jacks in each group, and a sensor holder is installed in each sensor jack and used for fixing each sensor.