PROBLEM TO BE SOLVED: To provide a free-moving state/fixed state changeover device for fishing and a float incorporating the same which can change the float to a free moving state or a fixed state freely with respect to a fishing line and can be easily handled by an amateur.SOLUTION: A free-moving state/fixed state changeover device 1A for fishing changes a float 5 to a free-moving state or a fixed state with respect to a fishing line 6 and comprises: a device body 2 a passing member 3 for selectively passing a float stopping member 7 fixed at a predetermined position of the fishing line 6 in a vertical direction according to a predetermined load and a locking member 4 for locking the float stopping member 7. When receiving a downward load from the float stopping member 7 by the weight of a lure 9 or the weight of a weight and a bait, the passing member 3 passes the float stopping member 7 downward. When receiving an upward load greater than the downward load from the float stopping member 7, the passing member 3 passes the float stopping member 7 upward.COPYRIGHT: (C)2015,JPO&INPIT【課題】ウキを釣り糸に対して遊動状態または固定状態に自由に変換することができるとともに、素人であっても取り扱いが容易な釣り用遊動固定可変装置およびこれを内蔵するウキを提供する。【解決手段】本発明に係る釣り用遊動固定可変装置1Aは、ウキ5を釣り糸6に対して遊動状態または固定状態にする釣り用遊動固定可変装置1Aであって、装置本体2と、釣り糸6の所定位置に固定されているウキ止め部材7を所定の負荷に応じて選択的に上下方向に通過させる通過部材3と、ウキ止め部材7を係止する係止部材4とを有しており、通過部材3は、ルアー9の重量または錘および餌の重量によりウキ止め部材7から下向き荷重を受けた場合にウキ止め部材7を下方へ通過させるとともに、ウキ止め部材7から下向き荷重よりも大きい上向き荷重を受けた場合にウキ止め部材7を上方へ通過させる。【選択図】 図2