1. An environment recognizing device to be used by a traveling type robot in an environment containing one or more than one obstacles in order to recognize the environment, the device comprising: a plane detecting device configured to compute a plane parameter on the basis of input images and to detect a plane on the basis of the plane parameter; an obstacle recognizing device configured to recognize an obstacle, if any, on the plane detected by the plane detecting device; and an environment map updating device configured to draw an environment map and/or update the existing environment map on the basis of information on the obstacle recognized by the obstacle recognizing device, wherein the plane detecting device is configured to detect a group of planes including a reference plane on which the robot is moving to be used as reference and one or more than one other planes substantially parallel to the reference plane, and the environment map updating device is configured to draw an environment map and/or update the existing environment map for the plane carrying an obstacle as recognized by the obstacle recognizing device out of the group of planes, wherein the plane detecting device includes: a plane computing device configured to sample three-dimensional data on three or more than three points out of the group of three-dimensional data obtained by converting the parallax image or the distance image input as the input image; a plane determining device configured to poll the plurality of plane parameters obtained from the plane computing device for a polling space and to determine the group of planes on the basis of the result of the polling; and a reliability parameter computational device for computing each of the three-dimensional data wherein the three-dimensional data whose reliability parameter is smaller than a predetermined threshold value is discarded, wherein, the obstacle recognizing device is configured to recognize an obstacle at least on the reference plane where the robot is moving out of the group of planes, and the environment map updating device is configured to draw an environment map of the reference plane where the robot is moving and/or update the existing environment map of the plane.