To perform a safe and secure procedure by more securely and accurately confirming the position of an indwelling needle tapped into a patient.

The indwelling needle 10 comprises a catheter 12, an outer needle hub 14 for holding the catheter 12, a puncture needle 16 to be inserted into the catheter 12, and an inner needle hub 18 for holding the puncture needle 16. The catheter 12 has a detection part 30 composed of a long body 28 wound around the outer surface of an inner tube 26 in an outer needle body 24. The detection part 30 is formed in a prescribed length along the axial direction of the inner tube 26. The outer surface of the detection part 30 has continuous projections and recesses to project toward the outer periphery, and a space 34 in which air is enclosed is formed inside the detection part 30.