Abstract: The large aperture space deployable antenna in orbit may encounter high-speed impacts from tiny space debris, which seriously threatens the safe service of the antenna on board. In order to study the dynamic response of the support structure of the space mesh deployable antenna and the parabolic cable-mesh during high speed impact, ANSYS/AUTODYN is selected to build a dynamic impact simulation model of the large aperture space mesh deployable antenna to simulate the dynamic response of the antenna during the impact with space debris of 2.5 mm-7.5 mm when the antenna is deployed and locked. The overall dynamic response of the structure, the damage state of key rods and parabolic cable network as well as the deformation performance of the structure as a whole are considered for impact velocities of 1.0 km/s-15.0 km/s and different impact position conditions. The results show that the structural response of the spatially expandable antenna structure to space debris impact can be divided into three stages: local vibration, cable restraint and overall vibration. A closer distance between the impact point and the centre of the antenna leads to more obvious structural response and larger average deformation of the structure. As the impact velocity increases, the average structural deformation of the spreading antenna tends to increase initially and then decrease. When the impact velocity is greater than 12.5 km/s, the impact area of the antenna is gradually reduced. The overall deformation of the spreading antenna is not negligible when it is impacted by tiny space debris at high velocity, which can provide reference for the subsequent structural protection and vulnerability analysis.