A body fluid sampling unit includes a puncture device including a needle having a sharp needle point and a drive mechanism for operating the needle to puncture a living body surface with the needle point, a tip including an introducing section for introducing a body fluid flowing out from a puncture portion of the living body surface punctured with the needle point, a test paper for detecting a predetermined component in the body fluid, and a tip body mounted to a component measuring device for measuring the quantity and/or property of the predetermined component detected by the test paper; and a case including a mechanism containing section for containing the puncture mechanism so that the needle point of the puncture mechanism can be moved by the drive means, and a sampling implement containing section for containing the body fluid sampling implement so that the tip can be taken out.