To provide a robot capable of executing the proper leg moving work in accordance with a surface condition of a road surface.

As the countermeasure to road surface in walking motion has its limit, this leg moving robot judges a condition of the road surface and a walking condition first of all, and then selects a proper foot part to autonomously exchange the leg part. An optimum walking motion pattern is determined under a condition determined on the basis of the selected foot part. Further a condition suitable for the relationship between the robot and the road surface is determined on the basis of a combination of the correspondence to the road surface in the walking motion and the correspondence to the road surface by the foot part. A moving range of the leg robot may be optionally mapped to record the road surface information.