To provide the torque-measuring device of a screwed body for measuring a screw torque while external and internal threads are actually screwed each other.

This measuring device is used to measure clamping force when an external thread Y and an internal thread X that are arranged opposingly are screwed relatively by at least two arrangement means that retain the external thread Y or the internal thread X at one end and are fixed to a body A that is essentially the same. The measuring device is provided with a top plate 1 having a contact part where the seat surface of the external thread Y touches and a fixation part for fixing to a body side and an axial force load cell 2, an internal thread torque load cell 4 for gear-locking the rotary direction of the internal thread X that is screwed to the external thread Y for retaining, a strain gauge H3 for converting distortion being generated in an internal screw torque load cell 4 due to the small rotation of a side for gear-locking the internal thread X, and a conversion part B for converting an electrical signal being generated by the strain gauge H3 to a torque.