The invention provides a semiconductor device which can reliably restrict transmission/reception of signals or a power source voltage between a reader/writer when peeled off after stuck to an object. The semiconductor device of the invention includes an integrated circuit and an antenna formed on a support base. In the semiconductor device of the invention, a separating layer which is overlapped with the integrated circuit and the antenna sandwiching an insulating film is formed on the support base. A wiring for electrically connecting the integrated circuit and the antenna, a wiring for electrically connecting semiconductor elements in an integrated circuit, or a wiring which forms the antenna passes through the separating layer.