To provide a biped walking robot which can perform smooth walking close to that of human beings and hardly falling by a shock from an external part with a simple structure.

Permanent magnets 4, 4A, 4B and 4C and iron plates 9, 9A, 9B and 9C are attracted respectively. A plate 5 on which the permanent magnets 4 and 4A are mounted is rotated by a motor 3 by 90°, the permanent magnet 4 and the permanent magnet 4A are slid onto an aluminum plate 8A from the iron plate 9 and the iron plate 9A, respectively, and attraction of the permanent magnet 4 and the iron plate 9, and attraction of the permanent magnet 4A and the iron plate 9A are released. From the state, motors 3B and 3C are rotated by 30° respectively so that the bottom surface of a right leg 1 is lifted to be in parallel with a floor surface 10, thus a right leg 2 can be lifted without the need of movement of the center of gravity. After the right leg 1 is lifted, motors 3b and 3E are rotated by 30° respectively so that the right leg 1 comes in parallel-contact with the floor surface 10, thereby forward movement can be attained.