An optical measurement apparatus includes a connector where a base end portion of a measurement probe introduced into a subject is connected, a light source unit that emits illumination light irradiated from a leading end of the measurement probe, an optical measurement unit that measures reflection light and/or scattering light of the illumination light incident through the measurement probe, a first optical path that transmits the illumination light emitted by the light source unit to the optical measurement unit, a second optical path that transmits, to the measurement probe, the illumination light emitted by the light source unit and transmits, to the optical measurement unit, reflection light and/or scattering light of the illumination light incident through the measurement probe, and an optical path switching unit that switches an optical path for transmitting the illumination light into the first optical path or the second optical path.