An environment recognizing device and an environment recognizing method can draw an environment map for judging if it is possible to move a region where one or more than one steps are found above or below a floor, a route planning device and a route planning method that can appropriately plan a moving route, using such an environment map and a robot equipped with such an environment recognizing device and a route planning device. The robot comprises an environment recognizing section including a plurality of plane extracting section 401 adapted to compute plane parameters from a parallax image or a distance image and extract a plurality of planes including the floor surface, an obstacle recognizing section 402 adapted to recognize obstacles on the plurality of planes including the floor surface and an environment map updating section 403 adapted to draw an environment map (obstacle map) for each of the planes on the basis of the result of recognition of the obstacle recognizing section 402 and update the existing environment maps and a route planning section 404 adapted to plan a route on the basis of the environment maps. The route planning section 404 selects a plane as route coordinate when an obstacle is found on it in the environment map of the floor surface but not found in the environment map of the plane.