To provide a biological component measuring apparatus that accurately and quickly measures a biological component.

This biological component measuring apparatus includes: a calibration solution storage tank for storing calibration solution that includes the same component as the biological component to be measured at a known concentration; a probe that includes an infiltration part for infiltrating the biological component to be measured from the outside to the inside, and that stores the calibration solution; a sensor for measuring the measuring object contained in a solution mixture of the calibration solution that has been supplied from the calibration solution storage tank into the probe, and the measuring object that has infiltrated through the infiltration part; a distribution switching means for selecting either a state (A) where the calibration solution is allowed to flow from the calibration solution storage tank to the probe and the solution mixture is allowed to flow from the probe to the sensor, or a state (B) where the calibration solution is allowed to flow from the calibration solution storage tank to the sensor without passing through the probe and the liquid in the probe is allowed to circulate; and a liquid circulation means for circulating the liquid in the probe.