Robotic lower-limb prosthesis plays an increasingly important role in amputees0 daily activities. One of the key programs in this research area is the human-prosthesis-environment interaction, and its solution is a crucial step towards reliable and smooth motions of the amputee wearing a robotic prosthesis in practical applications. In this paper, we overview the state-of-the-art of the robotic lower-limb prosthesis in the context of human-prosthesis-environment interaction. The overview includes bio-inspired mechanical structure design, control strategy, human intenting recognition, human-prosthesis interaction in complex environments, and sensory substitution for human-in-loop control. At last, existing challenges and future directions are discussed.