Abstract: In order to improve the efficiency and visualization level of airborne cable fault diagnosis in aviation system, airborne cable fault diagnosis technology and fault visualization technology are researched in this paper. In terms of fault diagnosis, an airborne cable fault diagnosis system based on spread spectrum time domain reflectometry is designed; at the same time, in order to solve the signal reflection issues caused by the impedance mismatch between the diagnostic system and the cable under test, the system also incorporates the impedance measurement and impedance matching functions, which adopts automatic balancing bridge technology to measure the cable's characteristic impedance and achieves impedance matching via an impedance matching network. Experimental results demonstrate that the system is able to complete the impedance measurement and fault diagnosis well. In terms of fault visualization, CATIA software is used to construct a digital 3D model of the airborne cable and an airborne cable fault visualization system based on CATIA secondary development technology is developed in this paper, which realizes the visual presentation of fault diagnosis results.