This sensor unit (1) comprises a radar (40), a substrate (41) on which the radar (40) is mounted, a cover member (12) that covers the radar (40) and the substrate (41), and an attachment member (13) for attaching the substrate (41) to the cover member (12) such that a transmission/reception surface (40a) of the radar (40) is set apart from the cover member (12) across a prescribed gap.
