As space technology rapidly evolves, space debris resulting from spacecraft activities is increasingly abundant. Billions of tiny space debris fragments exist, readily causing high-speed impact damage to truss structures and tension cables, thereby reducing the service life of the structures. To study damage, ANSYS software was used to create a simulation model, mimicking the dynamic response of a 2.5 mm spherical space debris impacting the cable net of truss structure of large-aperture space deployable antenna. The results showed that impact location and speed affected structural deformation and cable tension changes. The average deformation from impacting circumferential cables was greater than that of radial cables, and was unrelated to the distance between the impact point and the restraint point. For radial cables, the closer the impact location to the restraint point, the greater the average deformation. Cable deformation did not increase regularly with increasing speed, when a cable broke, it first tightened then loosened, and cables directly connected to the broken one also loosened, affecting antenna performance. It is recommended to install stress sensors on radial cables near restraint points during design to adjust tension, and to install damping devices on hoop cables to suppress vibrations and enhance service performance.