An obstacle sensor includes: a supersonic sensor for detecting an obstacle in a first range, the supersonic sensor including a substrate, a transmission device and a reception device disposed on the substrate; a detection element for detecting the obstacle in a second range; and a case. The reception device includes multiple reception elements. At least a part of the first range of the supersonic sensor is different from the second range of the detection element. The supersonic sensor and the detection element are disposed in the case.