Ankle rehabilitation robots represent an important branch of rehabilitation robotics, offering significant potential to improve the quality of life for patients with ankle dysfunction caused by stroke, sports injuries, and other conditions. This review first outlines the anatomy and range of motion of the ankle joint, compares conventional rehabilitation approaches with robot-assisted therapy, and highlights the clinical significance of ankle rehabilitation robots. It then systematically examines current research progress from two core perspectives: mechanical structure design and control strategies. In mechanical design, the performance characteristics of series versus parallel mechanisms are compared, the advantages and limitations of actuation methods such as electric motors and pneumatic artificial muscles are analyzed, and the application contexts of platform-based and wearable robots are discussed. In control strategies, the discussion covers motion control and human–robot interaction, beginning with fundamental position, velocity, and trajectory tracking control, and extending to intention-level and cognitive interaction. Finally, based on current research and clinical needs, future ankle rehabilitation robots are expected to evolve toward greater flexibility, intelligence, and universality, providing a theoretical foundation for future studies.