An outside sensor unit includes an outside sensor, a main bracket, a support bracket, and a cover member. The main bracket is attached to a vehicle body. The support bracket supports the outside sensor and is attached to the main bracket rotatably adjustably. The cover member covers an outer circumference in an outside detection direction of the outside sensor. The main bracket has a base wall that is attached to the support bracket rotatably adjustably and an attachment seat that is arranged at a position which is offset in the outside detection direction of the outside sensor with respect to the base wall. The cover member is attached to the attachment seat.