A terminal crimping structure includes a coaxial cable, a terminal fitting including a tubular conductor connecting portion coaxially interposed between a terminal connecting portion of an outer conductor of the coaxial cable and an insulator, a tubular crimping member that allows the terminal connecting portion to be coaxially interposed between the crimping member and the conductor connecting portion to crimp the terminal connecting portion onto the conductor connecting portion, and a tubular member that is stronger and harder than the conductor connecting portion and coaxially interposed between the conductor connecting portion and the insulator. Linear conductors of the terminal connecting portion include crushed portions that abut each other. The crushed portions are crushed until they are axially extended by an amount achieving a target crushed state in which an oxide layer is broken to obtain an exposed region of a new surface required for adhesion to the conductor connecting portion.