This paper deals with hypervelocity impacts of millimetre sized debris on space structures at velocity regime above 7 km/s. Millimetre sized debris present real threat to space structures since they cannot be tracked nor detected by radars. At the opposite, for larger debris, 5-10 cm sized, avoidance manoeuvre can be conducted remotely from earth to shift the space structure from the threat trajectory. Following the development of a new hypervelocity launcher at THIOT INGENIERIE, the present study presents hypervelocity impacts on different types of targets: single plate, whipple shield and honeycomb structure. Impact velocities ranging from 7 to 10 km/s have been reached. Specific diagnostic tools (very high speed camera, X-rays flash photography …) are used to analyse the tests. Results, in terms of ejecta projection, post-impact damage are presented. The effects of ejecta channelling in the case of honeycomb shield is highlighted.