A decorative component for a vehicle comprising a decorative body portion having a millimeter wave transmittance for millimeter waves from a millimeter wave radar device, wherein the decorative body portion is configured to be attached to part of a vehicle on a leading side in a transmitting direction of the millimeter wave from the millimeter wave radar device to decorate the vehicle, the leading side corresponding to a front side of the vehicle, and a heating sheet including a plastic sheet and a wire-shaped heater provided on the plastic sheet, the heating sheet including a main portion that is provided integrally with the decorative body portion, wherein a thickness of the decorative component in a front-rear direction is set uniform in at least a transmittance area of the millimeter wave, and the decorative body portion includes a base member made of a plastic material, a transparent member made of a plastic material, and a decoration layer provided between the base member and the transparent member and having a millimeter wave transmittance, wherein the plastic material for the transparent member allows appearance of the decoration layer from a front side of the vehicle, and at least the main portion of the heating sheet is arranged to be laminated with one of at least the base member and the transparent member, characterized in that the thickness of the decorative component in the front-rear direction is set uniform to a value substantially equal to a multiple by an integer of a value obtained by dividing a half wavelength of the millimeter wave by a square root of a relative permittivity of millimeter waves of the transparent member, "value substantially equal" referring to a thickness included in an error range of ± 0.2 mm, the main portion of the heating sheet is gently curved to bulge to a front side of vehicle, the transparent member is arranged on a front side of the base member in a state mounted to the vehicle, and at least the main portion of the heating sheet is arranged to be laminated with the transparent member from a front side of the transparent member, which is the side of the transparent member pointing towards the vehicle's front side in a state mounted to the vehicle such that it is located in the foremost section of the decorative body portion in a state mounted to the vehicle. a heating sheet including a plastic sheet and a wire-shaped heater provided on the plastic sheet, the heating sheet including a main portion that is provided integrally with the decorative body portion, wherein a thickness of the decorative component in a front-rear direction is set uniform in at least a transmittance area of the millimeter wave, and the decorative body portion includes a base member made of a plastic material, a transparent member made of a plastic material, and a decoration layer provided between the base member and the transparent member and having a millimeter wave transmittance, wherein the plastic material for the transparent member allows appearance of the decoration layer from a front side of the vehicle, and a base member made of a plastic material, a transparent member made of a plastic material, and a decoration layer provided between the base member and the transparent member and having a millimeter wave transmittance, wherein the plastic material for the transparent member allows appearance of the decoration layer from a front side of the vehicle, and at least the main portion of the heating sheet is arranged to be laminated with one of at least the base member and the transparent member, characterized in that the thickness of the decorative component in the front-rear direction is set uniform to a value substantially equal to a multiple by an integer of a value obtained by dividing a half wavelength of the millimeter wave by a square root of a relative permittivity of millimeter waves of the transparent member, "value substantially equal" referring to a thickness included in an error range of ± 0.2 mm, the main portion of the heating sheet is gently curved to bulge to a front side of vehicle, the transparent member is arranged on a front side of the base member in a state mounted to the vehicle, and at least the main portion of the heating sheet is arranged to be laminated with the transparent member from a front side of the transparent member, which is the side of the transparent member pointing towards the vehicle's front side in a state mounted to the vehicle such that it is located in the foremost section of the decorative body portion in a state mounted to the vehicle.