To make a finish of a clay tile roofing beautiful and also prevent rain water, snow melting water, dusts and flying objects from entering into the gaps between the adjoining flat plate tiles.

In a clay tile roofing structure where an overlapped part 1 of both right and left side edges and an under-lapped part 2 are overlapped each other to cover the clay flat roof A one by one, a packing material 4 having not only a compressibility and a restoration property but also a water-cut off property is interposed along the entire length between a gap of a protruded directional edge face of the above overlapped part and the side edge face of the adjoining clay flat roof.