The utility model discloses a power transmission line fault traveling wave monitoring device. The monitoring device comprises a housing (6). An upper part and a lower part are connected through a clamping groove to form the housing (6). A wire through hole (4) is arranged in the upper and lower splicing section of the housing (6). A power transmission line goes through the wire through hole (4). A fault traveling wave current sensor (2), a power supply unit (1) and a high-speed collection unit (3) are arranged in the housing (6). The power supply unit (1) supplies power for the high-speed collection unit (3). The output end of the fault traveling wave current sensor (2) is connected with the input end of the high-speed collection unit (3). The output end of the high-speed collection unit (3) is connected with an operational center through a wireless signal. The fault traveling wave current sensor is directly installed on the power transmission line, thus the distance between two detection devices can be decided according to a practical situation and is free from influence of the tower distance, the distance of the fault traveling wave current sensor is shortened, and thus fault positioning is accurate and rapid.