To provide a protective circuit for a substrate for a display which becomes to be high resistance at the application of a voltage in an inspecting process and also becomes to be low resistance at the application of a high voltage such as static electricity.

In a protective circuit 8 which is provided with the protective element 18 connected to an input-output terminal 17 and the auxiliary common wiring 19 connected to this protective element 18 in common, the protective element 18 is constituted of a semiconductor wiring in which a p type semiconductor part 181 and an intrinsic semiconductor part 182 are connected in series. Since the current-voltage characteristic of the protective element 18 by this constitution becomes nonlinear, the protective circuit becomes to be high resistance at the application of the voltage in the inspecting process and also becomes to be low resistance at the application of the high voltage such as static electricity.