A radar device is placed rearward of a vehicle decorative component in a vehicle. The decorative component is located in the path of radar waves emitted from the radar device, and has a two-layer structure with a back layer and a protective layer. The protective layer is made of a transparent resin material, and the back surface of the protective layer contacts the front surface of the back layer. The back layer is made of a resin material. The front surface of the back layer includes a front contact surface on which ground pattern is formed. The protective layer and the back layer have the same refractive index. Thus, the decorative component has an improved transparency of radar waves.