Abstract: A high tension release jumper cable and, more specifically, a safety device to be used when releasing the tension on a high tension cable guard rail system is provided. The high tension release jumper cable may be used by fire and rescue personnel to safely release the tension on a cable of a high tension cable guard rail system when necessary to conduct a rescue, recovery, or extraction. The high tension release jumper cable includes a safety cable with a high power clamp mounted on each end. The two clamps are clamped to the cable of the cable guard rail system while leaving slack in the safety cable. The cable of the cable guard rail system may then be slowly cut, while the clamps and safety cable ensure that the proper amount of tension is safely released from the cable.