PROBLEM TO BE SOLVED: To reduce more measurement errors of a blood component measuring device by calibrating with a structure for calibration and to improve its measurement accuracy.SOLUTION: The structure 10 for calibration includes a body part 24 having a light scatterer 22 therein and a flow cell 28 filled with a calibration liquid 26. The flow cell 28 comprises a transmitter 40 to transmit a near-infrared light irradiated from a light emission part 18 of the blood component measuring device 12 and a tube 42 to be connected to the transmitter 40. A transmission part includes a first transmission part 44 with a short optical path length of the near-infrared light and a second transmission part 46 with a long optical path length of the near-infrared light to be connected to the first transmission part 44, which switches a position of the transmitter 40 to the light emission part 18 by sliding displacement of the structure for calibration 10.COPYRIGHT: (C)2012,JPO&INPIT【課題】較正用構造体を用いて較正を行うことによって血液成分測定装置の測定誤差をより一層低減し、測定精度の向上を図る。【解決手段】較正用構造体10は、内部に光散乱体22を有した本体部24と、較正液26の充填されたフローセル28とを備え、前記フローセル28は、血液成分測定装置12の発光部18から照射される近赤外光を透過させる透過体40と、該透過体40に接続されるチューブ42とからなる。そして、透過部は、近赤外光の光路長が短い第1透過部44と、前記第1透過部44と接合され前記近赤外光の光路長が長い第2透過部46とを備え、較正用構造体10スライド変位させることによって発光部18に対する透過体40の位置を切り換える。【選択図】図1