The present invention provides an in-vivo indwelling instrument in which a stretch resistant member or a resin tip at a distal end part of a coil does not easily stray from the coil, a delivering system for the in-vivo indwelling instrument, and a method for producing the in-vivo indwelling instrument. An in-vivo indwelling instrument (10) includes: a coil (11) that is formed by winding a wire (12) and extends in a distal and proximal direction； a resin tip (20) that is connected to a distal end part of the coil (11)； and a stretch resistant member (21) that is provided in a lumen of the coil (11) and is connected to the resin tip (20). The coil (11) includes a contacting part (13) which is the distal end part and in which parts of the wire (12) that are adjacent to each other are in contact with each other by a length of at least one round or more, and a separating part (14) which is located on a proximal side of the contacting part (13) and at which the parts of the wire (12) that are adjacent to each other are separated from each other, and a part of the resin tip (20) exists in the separating part (14).
