To provide an ablation needle device that can be used for a transvenous ablation treatment for primary aldosteronism. An ablation needle device according to the present invention is an ablation needle device intended for an ablation treatment of an adrenal tumor with transvenous introduction of an injection needle into an adrenal gland. The ablation needle device includes a metal injection needle 10 including a pointed tubular distal portion 11 and a tubular proximal portion 12, and a grip portion 20 attached to a proximal side of the injection needle 10. The proximal portion 12 of the injection needle 10 is given flexibility by forming a helical slit 14 in a distal region 12A of the proximal portion 12. An outer surface of the proximal portion 12 is coated with resin 16. A distal end of the distal portion 11 of the injection needle 10 is closed. A plurality of fine holes 15 are formed in an outer surface of the distal portion 11 including the closed part 13. The grip portion 20 has a liquid-injection port 25 for supplying liquid into the lumen of the injection needle 10.
