PROBLEM TO BE SOLVED: To provide a disposable blood collecting instrument for stably securing a sufficient amount of blood with one puncturing operation.SOLUTION: The circumferential part of an opening 38 in housings 10, where the distal end 63 of a puncture body 62 of a lancet 11 stored inside the housings 10 is projected by energization force of a spring member 12, is provided as a transparent visible part 59 for visually recognizing the inner part. The spring member 12 is stored in the housing more on the side closer to the retracting direction of the puncture body 62 than the position of the distal end 63 of the puncture body 62 which is put into the housings 10 after a puncture operation.COPYRIGHT: (C)2011,JPO&INPIT【課題】一回の穿刺操作で十分な血液量を安定的に確保し得るディスポーザブル型採血器具を提供する。【解決手段】ハウジング10内に収容されたランセット11の穿刺体62の先端63がばね部材12の付勢力により突出する、ハウジング10の開口部38の周辺部分を、内部を視認可能な透明性を有する可視部59とする。また、穿刺作動後にハウジング10内に入り込んだ穿刺体62の先端63の位置よりも、穿刺体62の後退方向側のハウジング内に、ばね部材12を収容して、ディスポーザブル型採血器具を構成した。【選択図】図9