Abstract: Aiming at the impact problem of spacecraft by micrometeoroid/orbital debris（MMOD）at hypervelocity，monitoring of the hypervelocity impact damage to honeycomb sandwich structures was studied.A method was proposed to co-cure carbon nanotube（CNT）film on the surface of honeycomb sandwich structure to enable it have self-sensing capability to detect and identify hypervelocity impacts and their associated damage by using electrical tomography technique.Experimental studies were conducted with a two-stage light gas gun to perform hypervelocity impacts to the self-sensing honeycomb sandwich structures.By injecting tiny currents into the CNT sensing layers before and after hypervelocity impacts，the conductivity changes caused by hypervelocity impacts were reconstructed by the change of boundary voltages，providing valuable information about the impact and damage.The experimental results show that，the CNT sensing layers have good performance，and the reconstructed images of conductivity changes can reflect the number，locations and approximate sizes of the damage，validating the effectiveness of the proposed method and providing a new technical method for spacecraft to monitor hypervelocity impacts.

Key words: honeycomb sandwich structure, hypervelocity impacts, carbon nanotube films, electrical tomography, damage identification