A display device manufacturing method according to the disclosure includes the steps of forming a first resin layer serving as a first flexible substrate on a first mother substrate, forming a first light-emitting layer on the first resin layer, and forming, on the first light-emitting layer, a first encapsulating layer encapsulating the first light-emitting layer, forming a second resin layer serving as a second flexible substrate on a second mother substrate, forming a second light-emitting layer on the second resin layer, and forming, on the second light-emitting layer, a second encapsulating layer encapsulating the second light-emitting layer, bonding the first mother substrate and the second mother substrate with a buffer sheet interposed between the first mother substrate and the second mother substrate so that the first encapsulating layer and the second encapsulating layer face each other, peeling the first resin layer from the first mother substrate in a state where the first resin layer and the second resin layer are layered with the buffer sheet interposed between the first resin layer and the second resin layer, and bonding a first support film to the first resin layer.