A blood test device whereby a used sensor can be discarded without staining the holding part after the completion of blood measurement. In this device, a blood sensor (23), which collects blood oozing out from the punctured skin and analyzes the blood components, is held between a first holder (25a) and a second holder (25b). The second holder (25b) is provided in a movable manner along the direction of closing to and separating from the first holder (25a). By a pressing projection (20b), the second holder (25b) is moved so that the second holder (25b) is separated from the first holder (25a). At the same time, the blood sensor (23) is separated from both of the first holder (25a) and the second holder (25b) and supported by supporting claws (20c). Thus, a gap is formed between the first holder (25a) and the second holder (25b) as described above.