There is provided a multi-layered structure forming method comprising: (A) forming a first insulating material layer containing a first photo-curing material on a substrate; (B) semi-hardening the first insulating material layer by radiating light having a first wavelength to the first insulating material layer; (C) forming a conductive material layer on the semi-hardened first insulating material layer by ejecting droplets of a conductive material to the semi-hardened first insulating material layer from a nozzle of a liquid droplet ejecting apparatus; (D) forming a second insulating material layer containing a second photo-curing material so as to cover the semi-hardened first insulating material layer and the conductive material layer; and (E) forming a first insulating layer, a conductive layer positioned on the first insulating material, and a second insulating layer covering the first insulating layer and the conductive layer by simultaneously heating the first insulating material layer, the conductive material layer, and the second insulating material layer.