1. An autonomous mobile body which moves in a movement region while recognizing a self-position of the autonomous mobile body, the autonomous mobile body comprising: a sensor section for measuring, by emitting a beam, a distance from the sensor section to each of a plurality of obstacles located in the movement region; and a self-position recognizing section for recognizing the self-position by (i) calculating a self-position candidate in accordance with the distance and designating the distance as a sensor distance, (ii) comparing the sensor distance with a map distance which extends from the self-position candidate to the each of the plurality of obstacles and which is calculated in accordance with an environment map containing information on a position of the each of the plurality of obstacles and (iii) correcting the self-position candidate, the self-position recognizing section including a clustering section for (i) grouping distance measurement points of the each of the plurality of obstacles into clusters, the distance measurement points having been measured by use of a beam emitted from the sensor section and (ii) recognizing the each of the plurality of obstacles.