This paper presents a robotic foot mechanism based on truss structure for walking robots and analyzes its effectiveness for compliant walking. The specified foot mechanism has been modeled by observing the structure and behavior of human foot. The frame of bone used in the human foot is considered as a truss, and the ligaments of the human foot are represented as a simple stiffness element. So such a robotic foot has an advantage to moderate the impact of foot when a walking robot takes a step. As a result, it is practically expected that the proposed robotic foot mechanism can contribute to reduce the physical fatigue of walking robots.