This invention provides a bodily-fluid-sample collection instrument that has a simple structure, comprising just the following two components: a bodily-fluid collection cap provided with a means for collecting a bodily fluid such as blood without using a fiber rod and a bodily-fluid dilution container for diluting the bodily fluid with a bodily-fluid-diluting buffer solution. Said bodily-fluid-sample collection instrument is characterized by comprising the following: a bodily-fluid collection cap that comprises a cylindrical bodily-fluid collection section and a cap section and a bodily-fluid dilution container into which the bodily-fluid collection section can be inserted and the bodily-fluid collection cap screwed closed so as to seal the bodily-fluid dilution container. The bodily-fluid-sample collection instrument is also characterized in that: the inside of the bodily-fluid collection section has a slope along which the collected bodily fluid flows and a concavity for holding the bodily fluid that has flowed from said slope and the ratio (surface area/volume) of the surface area (in mm2) that the bodily-fluid sample contacts to the container volume (mm3) that the bodily-fluid sample can fill is greater than or equal to 1.1 (mm2/mm3).La présente invention concerne un instrument de collecte déchantillon de fluide corporel qui a une structure simple, comprenant uniquement les deux éléments suivants : un capuchon de collecte de fluide corporel ayant un moyen pour collecter un fluide corporel, tel que le sang, sans utiliser de tige en fibre et un récipient de dilution de fluide corporel pour diluer le fluide corporel avec une solution tampon de dilution de fluide corporel. Ledit instrument de collecte déchantillon de fluide corporel est caractérisé par le fait quil comprend les éléments suivants : un capuchon de collecte de fluide corporel qui comprend une section de collecte de fluide corporel cylindrique et une section capuchon et un récipient de dilution de flu
