The present invention provides a printer and printing method that forms a lenticular lens or a transparent structure based on pseudo-embossment printing or the like on paper having penetrability, and an inkjet printer performs: with respect to a base material having a characteristic of being penetrated by radiation-curable ink, an undercoating step of using radiation-curable transparent ink to form a thin undercoat layer; an undercoat curing step of irradiating the formed undercoat layer with radiation to completely solidify the thrilled undercoat layer; a transparent structure forming step of using the radiation-curable transparent ink to form a spacer layer and microlens layer as a desired transparent structure on the solidified undercoat layer; and a transparent structure curing step of afterward further irradiating the radiation to cure the formed spacer layer and microlens layer.