The medical wire (1) according to the present invention is composed of a plurality of main strands for the purpose of generating a desired driving force with high response at the distal end side even in a medical device having a flexible inserting portion A main element part (10) extending over the entire length of the main element part (10), one or more sub element parts (10) arranged on the outer periphery of the main element part (10) and fixed to the main element part (2) having a cross section area relatively smaller than the diameter of the main element wire and having a diameter larger than twice the diameter of the main element wire and a second region (2) having a diameter larger than the first region (2) And a second region having a cross-sectional area.軟性の挿入部を備えた医療機器においても、先端側で高い応答性で所望の駆動力を発生させることを目的として、本発明に係る医療用ワイヤ(1)は、複数の主素線により構成され全長にわたる主素線部(10)と、主素線部(10)の外周に配置されて主素線部(10)に固定され、副素線により構成される1以上の副素線部(20)とを備え、副素線の径が主素線の径の2倍以上であり、相対的に横断面積が小さい第1領域(2)と、該第1領域(2)よりも大きい横断面積を有する第2領域とを有する。
