The development of novel high-performance hypergolic fuels is crucial for the advancement of the aerospace industry. Although hydride-containing compounds offer excellent combustion properties and a short ignition delay time, their inherent instability and strong reducing nature have hindered their widespread application. Herein, we report the synthesis and characterization of an energetic, atomically precise copper hydride cluster, Cu11H3(5N-dpf)6(OAc)2, denoted as Cu11H3. This cluster exhibits exceptional hypergolic performance and good stability. When paired with high-test peroxide (HTP, >90% H2O2), Cu11H3 demonstrates a short ignition delay time of 16 ms and achieves a high specific impulse of 254 s. Both experimental and theoretical studies suggest that the hydrides play a pivotal role in the ignition process through interactions with protons from H2O2, leading to hydrogen evolution and accelerated combustion. This research provides valuable insights for the design and development of novel, environmentally benign solid hypergolic fuels for propulsion applications.