Abstract: The poor damping performance of polydimethylsiloxane (PDMS), arising from its low interchain friction and regular molecular structure, motivates the improvement of its energy dissipation performance. Herein, hyperbranched siloxane clusters (TC) were synthesized and then used with hydroxyl-terminated polydimethylsiloxane (OH-PDMS) to prepare polyborosiloxane (PBS), which was further blended with PDMS to yield a high-damping, impact-resistant double-network silicone rubber. Effects of the TC addition amount (Percentage of TC mass to OH-PDMS mass) and the mass ratio of PDMS to PBS network on the mechanical properties, rheological properties, and energy dissipation performance of the double-network silicone rubber were systematically investigated. When the TC addition amount was 2% and the mass ratio of PDMS to PBS network was 3/7, the double-network silicone rubber exhibited the best overall performance, achieving a modulus increase of up to 10 times under frequency variation, an elongation at break of 210%, and a loss factor higher than 0.3. Moreover, its damping performance remained stable over a wide temperature range of 25–125 ℃ under low-frequency conditions, opening a new avenue for the design of highly impact-resistant, high-damping elastomers with a broad temperature window.