A rehabilitating pipe is laid inside an existing pipe to rehabilitate the existing pipe. Support members are intergrally connected to an inner wall surface of the existing pipe so that loop portions of the respective support members extend from the inner wall surface of the existing pipe. The rehabilitating pipe is assembled inside of the existing pipe by mutually coupling segments of the rehabilitating pipe in a longitudinal direction of the existing pipe by inserting coupling members through connecting through-holes of the segments and through the loop portions of the respective support members to thereby support the assembled rehabilitating pipe so that the rehabilitating pipe remains inside of the existing pipe after assembly to rehabilitate the existing pipe.