As the first stage of biped walking adapting to an unknown uneven surface using an anthropomorphic biped walking robot, this paper introduces a special foot mechanism with shock absorbing material that stabilizes biped walking and acquires position information on the landing surface. The new foot has three functions: (1) a function to obtain information on the position relative to a landing surface; (2) a function to absorb the shock of the foot's landing; (3) a function to stabilize changes in the support leg. Two units of the foot mechanism were produced, a biped walking robot WL-12 RVI that had the foot mechanism installed inside it was developed, and a walking experiment with WL-12 RVI was performed. As a result, decreased vibration around the pitch axis, decreased torque demands on ankle actuators on the pitch axis, increased dynamic biped walking success probability, and acquired landing surface information was achieved.