PURPOSE: To provide a structure of soldering a conductor covered with an insulating material to a terminal, with which the working effectiveness is enhanced, risk of damaging or severance of the conductor is eliminated, and the mechanical strength of the connection part is increased.

CONSTITUTION: In the condition that the inner conductor 31 is covered as it has been, an inner sheath insulation 32 is pinched resiliently between the elastic deformation part 43 of a resilient connection terminal 40 and its pinching piece 44 without requiring labor of stripping the inner sheath insulation 32 and for precluding the risk of damaging or severance of the inner conductor 31. The inner sheath insulation 32 is melted by subjecting this resiliently pinched part to a soldering process, and the elastic deformation part 43 advances inside the inner sheath insulation 32, which has been melted by the elastic restoration force, and touches the conductor 31 located inside. The touched conductor 31 is connected with the part 43 by solders 60. Hardened insulating material 32a after melting attaches to the solders 60 to increase the mechanical strength.