a floor rotating arm, one end of the floor rotating arm being mounted on a floor surface so as to be rotatable around a first rotation axis by means of a floor rotating arm rotating mechanism;

a stand mounted on the other end of the floor rotating arm so as to be rotatable around a second rotation axis by means of a stand rotating mechanism;

an arm holder mounted on the stand so as to be rotatable around a third rotation axis by means of a arm holder rotating mechanism;

a C-arm mounted on the arm holder so as to be slidly rotatable around a fourth rotation axis by means of a C-arm sliding mechanism;

an X-ray collimating device of an X-ray generating unit mounted on one end of the C-arm, and an X-ray detecting unit mounted on the other end of the C-arm, the X-ray collimating device and the X-ray detecting unit being rotatable around a fifth rotation axis by means of a axis rotating mechanism;

an operation unit in which operation buttons are arranged; and

a C-arm holding apparatus driving unit which supplies a driving signal to drive the floor rotating arm rotating mechanism, the stand rotating mechanism, the arm holder rotating mechanism, the C-arm sliding mechanism, or the axis rotating mechanism through an angle proportional to an operation time of the operation buttons of the operation unit,

wherein the C-arm holding apparatus driving unit supplies a driving signal to move the fifth rotation axis along a line orthogonal to a longitudinal direction of the subject in accordance with an operation time of a selected button of the operation buttons of the operation unit,

the apparatus further comprising a control unit which controls the C-arm holding apparatus driving unit,

wherein the control unit controls the C-arm holding apparatus driving unit such that the fifth rotation axis moves along the line orthogonal to the longitudinal direction of the subject by interlocking a rotation around the first rotation axis of the floor rotating arm with a rotation around the second rotation axis of the stand.