In order to detect various targets with greater accuracy, the disclosed obstacle detection device is provided with: a reception antenna unit having a plurality of combinations of reception antennas for detecting the position of a target in the horizontal and vertical directions, in which a plurality of reception antennas are arrayed in the horizontal direction in a manner such that some of the reception antennas are offset in the vertical direction; and a detection means for changing the combination of reception antennas and detecting a target multiple times. As a result, it is possible to increase the target detection precision by comparing at least two detection results from the detection means.