An electronic device substrate includes an insulating plate base, an electronic circuit formed on one surface of the base, and a conductive film formed on the other surface of the base and having electrical conductivity. The electronic device substrate is completed through a manufacturing process including charge-removal movement in which removal of a charge of the base is combined with movement of the electronic device substrate. In the charge-removal movement, the electronic device substrate is moved with being supported by a substrate support part that has electrical conductivity and is grounded. The substrate support part abuts the conductive film during the charge-removal movement.