Quantum repeaters hold promise for scalable long-distance quantum communication. The basic building block is a quantum light-matter interface that generates non-classical correlations between light and a quantum memory. Significant progress has been made in improving the performance of this interface, but further development of quantum repeater is hindered by the difficulty of integrating the key capabilities into a single system. Here we report a high-performance interface with an efficiency and lifetime that fulfil the requirement of a quantum repeater. By confining cold atoms with a three-dimensional optical lattice and enhancing the atom-photon coupling with a ring cavity, we observe an initial retrieval efficiency of 76 ± 5% together with a 1/e lifetime of 0.22 ± 0.01 s, which supports a sub-Hz entanglement distribution of up to 1,000 km through the Duan-Lukin-Cirac-Zoller (DLCZ) protocol. Together with an efficient telecom interface and moderate multiplexing, our result may enable a quantum repeater system that beats direct transmission in the near future.