Interdental cleaning tool with a simple configuration that can effectively prevent the core base material from being bent during insertion or interdental cleaning without reducing the productivity of the interdental cleaning tool. And its manufacturing method. A cleaning portion recess (through the cleaning soft portion (21) and forming a recess (14a) in the core base material portion (12) in each of the first side portion and the second side portion of the cleaning portion (2). 14) are formed at intervals in the axial direction of the cleaning soft part (21), and at least one of the plurality of cleaning part recesses (14) is a core formed on the core base part. The opening shape of the base portion recess is long in the axial direction of the cleaning portion.簡単な構成で、歯間清掃具の生産性を低下させることなく、歯間への挿入時や歯間清掃時における芯基材部の折れの発生を効果的に防止し得る、歯間清掃具及びその製造方法を提供せんとする。 清掃部（２）の第１側部と第２側部のそれぞれに、清掃用軟質部（２１）を貫通して、芯基材部（１２）に凹部（１４ａ）を形成する清掃部凹部（１４）を、清掃用軟質部（２１）の軸方向に間隔をあけてそれぞれ複数個形成し、複数の清掃部凹部（１４）のうちの少なくとも１つが、前記芯基材部に形成される芯基材部凹部の開口形状が前記清掃部の軸方向に長い形状である。
