Extra-high voltage transmission lines and cables are subject to irregular vibration due to icing or unusual weather conditions, which is potentially hazardous to the safety of the towers and the structural strength of the wires. Most of the current monitoring methods use electronic acceleration sensors, which have low sensitivity, poor signal-to-noise ratio, troublesome installation process, need for additional power supply and other issues. Distributed fibre optic vibration demodulation method is currently more advanced sensing technology, can achieve long distance, large scale, multi-dimensional online monitoring and structural safety warning. The laser fibre sensing distributed Michaelson coherent technology is used to develop a cable vibrate sensor, which can achieve the vibrate monitoring of cables and towers. The sensor consists of an elastic thin-walled cylinder, a mass ring, a fixed ring, and a sensing fibre, which uses a highly sensitive fine optical fibre and a coupler to build a laser-fibre Michelson coherent optical path, which is very sensitive to vibration signals, and encapsulates the interferometer into a specific metal casing to achieve the encapsulation and integration of the vibrate monitoring sensor. The optical system of this laser fibre sensor has the advantages of high sensitivity and high signal-to-noise ratio. Using the differential cross-multiplication demodulation algorithm for many experiments and results analysis, the demodulation output of the linear correlation coefficient of up to 0.95 in the frequency of 10Hz ∼ 200Hz under the conditions of the vibrate, suitable for high-voltage towers and cables for online monitoring of the vibrate.