A robot includes a body, a wheel having a ground contacting surface when moving, and a wheel drive mechanism that drives the wheel so as to advance from a housing space provided in the body to an exterior and withdraw. The wheel drive mechanism causes the wheel to withdraw to the housing space in a non-ground contacting state when a housing condition is satisfied. The body has a ground contacting bottom face that comes into contact with the ground when the wheel is housed in the housing space in a non-ground contacting state.