An in-vehicle camera unit has a body to which a lens is attached and prevention members that prevent water drops from falling on the lens. Specifically the body has a top surface where the lens is arranged, a front surface of the lens being exposed to an outside of the body. The top surface has an oblique portion extending from the periphery of the lens backward of the lens. The oblique portion is oblique in such a way as to be away from the optical axis 13a of the lens with increasing distance from the lens backward. The prevention member is provided in or on the oblique portion across an oblique direction of the oblique portion.