To precisely determine the insertion depth of an introduction sheath into an organism by a simple method.

This medical appliance set 1 is provided with a needle tube 2 and the introduction sheath 3. The needle tube 2 is provided with a needle tube body 22 formed with a sharp needle tip 21 at its distal end and a hub 23 connected to the proximal end of the needle tube body 22, and the outer circumferential face of the needle tube body 22 is formed with a scale 24 indicating the puncture depth of the needle body 22 into the organism. The outer circumference part of the needle tube body 22 is mounted with an index 25 movable in the longitudinal direction of the needle tube body 22. The introduction sheath 3 is constituted of a tubular sheath body 32 with flexibility and the hub 33 connected to the proximal end of the sheath body 32. The outer circumferential face of the sheath body 32 is formed with a scale 34 indicating the insertion depth of the sheath body 32 into the organism. The both scales 24 and 34 are in compliance with the same calibration.