In order to achieve low cost of manufacture of a display device by reducing the use of primary material used in a manufacturing process of a display device and saving labor taken for a vacuum process, according to the invention, liquid droplets containing conductive particles are ejected on a film being processed by using a first liquid droplet ejecting apparatus having a liquid droplet ejecting head provided with a plurality of liquid droplet ejecting orifices, thereby a conductive film is formed. After that, a resist pattern is locally formed on the conductive film by using a second liquid droplet ejecting apparatus having a liquid droplet ejecting head provided with a plurality of liquid droplet ejecting orifices. The conductive film is etched with the resist pattern as a mask to form a wiring.