An optical measurement apparatus, to which a base end portion of a measurement probe introduced into a subject is connected so that scattering light from the subject through the measurement probe can be measured, includes: calibration member serving as an irradiation target of illumination light when a calibration process is performed for the measurement probe using the illumination light from the measurement probe; an insertion portion where a leading end of the measurement probe can be inserted; a housing portion that communicates with the insertion portion and accommodates the calibration member movably along a penetration direction of the insertion portion; a detection unit that detects insertion of the measurement probe when the calibration member reaches a predetermined position in the housing portion by the insertion of the measurement probe through the insertion portion; and a control unit that performs control for initiating the calibration process when the detection unit detects the insertion of the measurement probe.