Provided is an overhead line fault positioning monitoring device, belonging to the field of power grid fault detection apparatus. The device includes a base and a fault detection module arranged on the base, the base is provided with an inclined plane, a semi-cylindrical flip cover is arranged corresponding to the inclined plane, the base is connected with the flip cover through a locking slide lock, the fault detection module includes two through type current transformers, one is an electricity obtaining ring and the other is a measuring ring, the winding of the electricity obtaining ring is connected to the input port of the power supply of the fault detection module, the winding of the measuring ring is connected to the monitoring signal input port of the fault detection module, each current transformer is divided into an upper half ring and a lower half ring that are fixed on the base, and the upper half ring is correspondingly arranged on the flip cover. The connection of the base and the flip cover is realized by the locking slide block structure, so that the installation is convenient; the double current transformers effectively solve the contradiction between the induction electricity obtaining and measurement, so that the measurement precision is improved while the normal work of the device is guaranteed, and the device has the characteristic of high fault capturing accuracy.