An indwelling needle is provided which has a simple structure and is capable of securely mounting a needle tip protective tool on the tip portion of an internal needle. The indwelling needle A consists of an external needle 10 including a cannula 11 and a housing 12, an internal needle 20 including a metal needle 21 and a hub 22 and a needle tip protective tool 30. The needle tip protective tool 30 is mounted on the housing 12 with the metal needle 21 inserted into an inner section so that the metal needle 21 can be removed together with the internal needle 20 from the external needle 10. A main body 31 of the needle tip protective tool 30 has a cylindrical shape. Window sections 34a, 34b are provided on opposing circumferential surfaces of the main body 31. On a rear end marginal section of window section 34a, a movable gripped section 32 is provided whose outer section 32b extends toward the outside of the main body 31 and whose end consists of a grip section 32c. The gripped section 32c and the grip section 33c are latchable with each other within main body 31.