The invention relates to a torsional strength testing torsion testing machine, which comprises a rack and an operation table, wherein the rack is provided with the operation table and a guide rail, the guide rail is provided with a test operation table, the test operation table is provided with an operation rod and an emergency stop component, an opening/closing rod is arranged beside the operation rod, positioning blocks are arranged between the test operation table and the guide rail and are positioned on the bottom portion of the test operation table, and the positioning block is made from an alloy steel material. According to the present invention, the top portion of the guide rail is provided with the baffle, such that the distance between the clamping jaw and the clamping member can be well controlled, the impact of the clamping jaw on the clamping member due to the over high force applying is prevented, the use safety of the clamping jaw and the clamping member is ensured, and the damage on the clamping jaw and the clamping member is avoided; and the hand wheel drives the screw rod to control the movement of the clamping jaw, such that the movement speed is uniform, and the torsional strength testing result of the electric cable is accurate.