PURPOSE: To facilitate the connecting work of a pipe by forming a pipe connecting member with a cylindrical shape memory alloy, and allowing it to memorize a shape so that both end sections are expanded in the radial direction when it is heated to the transformation temperature or above.

CONSTITUTION: Recesses 22 and 32 are formed on inner peripheries of butt sections of pipes 2 and 3, and a pipe connecting member 1 having tapers 14 and 15 and both end sections 11 and 13 is coupled with these recesses 22 and 32. The pipe connecting member 1 is made of cylindrical member, outer diameters of both end sections 11 and 13 in the axial direction are formed larger than the outer diameter of an intermediate section 12, and it is made of a shape memory alloy. When it is heated to the martensite transformation temperature or above, both end sections 11 and 13 are expanded in the radial direction, and the intermediate section 12 is shrunk in the axial direction. The connecting work of a pipe can be easily and efficiently performed. No finishing work is required after implementation.