PROBLEM TO BE SOLVED: To have cold insulator attachably and detachably positioned and supported at a place without direct contact with fish or the like so that cold air always flows down from above the fish, and to secure a large store chamber, and to maintain cooling function.SOLUTION: A portable cooler box includes: a case 2 having a store chamber for fish and having a top being open a lid 3 which opens and closes the top and a supporting mechanism 6 supporting the cold insulator near the upper open edge above the store chamber for fish in the case. The supporting mechanism 6 includes: recessed parts 10 being positioned between the two opposing inner walls of the store chamber and being each formed in connection with the opening of the case a large mesh shelf means 12 supporting and places a cold insulator at the upper part of the store chamber, while attachably and detachably engaging with the recessed parts of the two opposing walls at the same time, and contains a large mesh frame material or a stay member for supporting the approximately whole lower surface of the cold insulator supported above the store chamber, with the approximately whole lower surface being exposed to the bottom side of the case and a fall arrester 14 for preventing the cold insulator placed at the large mesh shelf means from falling downward.COPYRIGHT: (C)2013,JPO&INPIT【課題】保冷材に直接に魚が触れない位置で冷気が常に魚の上方から下降する位置に保冷材を着脱自在に配置支持させ、収容室を広く確保し、保冷機能を維持させる。【解決手段】魚等の収容室を有し上面を開口したケース体2と、開口を開閉する蓋3と、ケース体の魚等の収容部の上方位置となる収容室の上部の開口縁近傍に保冷材を支持する支持機構6を設ける。支持機構6は、収容室の対向両壁の対向する内壁位置であって、ケース体の開口に連続してそれぞれ設けられた凹部10と、対向両壁の凹部に着脱自在かつ同時に係合しつつ収容室の上部に保冷材を載置支持する粗目棚手段であり、収容室の上部に支持された保冷材の略下面全体をケース体の底壁側に露出させた状態で支持する粗目枠材又はステー部材を含む粗目棚手段12と、保冷材を粗目棚手段に載置させた状態で保冷材の下方への落下を防止する落下防止装置14と、を備える。【選択図】図1