A blood analysis apparatus for obtaining blood for analysis from the skin of a patient with a controlled degree of lancing. The apparatus including a cartridge and a driver. The cartridge includes a cartridge case and a lancet. The lancet has a tip and is housed in the cartridge case. The lancet can be driven to extend the tip outside the cartridge case through an opening for lancing the skin of the patient to yield blood. The driver drives the lancet to move the tip distally to lance the skin. The driver is triggerable by the skin which is to be lanced exerting a force exceeding a preset amount against the triggering mechanism of the apparatus, to drive the lancet toward the skin.