<p>Provided is a member conjunction structure of which working can be easily performed and which is suitable for a roof structure. The member conjunction structure comprises a frame roof (1) forming a lip (1f) bent from the end edge of a linearly extending outer flange (1b), a panel roof (2) having an edge put on the outer flange (1b), and a trim roof (3) put on the edge of the panel roof (2) and covering the lip (1f) of the outer flange (1b). The material derived from the portion forming the outer flange (1b) is mixed with the materials derived from the edge of the panel roof (2) and the portion of the trim roof (3) overlapped with the panel roof (2) by a frictional heat and a plastic flow so as to form an assimilation layer (16).</p>
