A multi-layered window structure of the present invention includes: a first window pane made of glass; a second window pane made of polycarbonate, being smaller in both height and width than the first window pane, and formed to a thickness of 5 mm to 30 mm; a hollow annular spacer disposed so as to extend along edges of the first window pane and the second window pane, and having holes in a side wall facing an air layer between the first window pane and the second window pane; and a primary sealer being an elastic body, with a thickness of 0.5 mm or more and a width of 6 mm or more, that extends along the edges of the first window pane and the second window pane, and is disposed between the first window pane and the spacer, and between the second window pane and the spacer.