Abstract: Single crystal is the most advantageous of the crystalline states of halide perovskites. It displays better optical and electrical capabilities than polycrystalline films and microcrystals due to their inherent structural advantages, such as free grain boundaries, long-range ordered structure, and high orientation. Single-crystal perovskite materials can theoretically enable optoelectronic devices with higher performance and stronger stability. In this review, the intrinsic physical properties of perovskite single crystals are analyzed. The most recent advances in single-crystal optoelectronic devices are reviewed, and the design principles of the devices under different application conditions are revealed. It provides potential solutions for remaining challenges, and it is expected to accelerate the development of perovskite based optoelectronic devices.