An optical measuring device comprising: a light source unit configured to emit light for measuring a living tissue; a measurement probe including a fiber bundle, the said fiber bundle including an illumination fiber that is configured to propagate light from the light source unit to a distal end as illumination light and illuminate the living tissue with the illumination light, and a plurality of light-receiving fibers configured to receive return light of the illumination light illumined by the illumination fiber and reflected and/or scattered at the living tissue; a detection unit configured to receive the return light of the illumination light detected by the plurality of respective light-receiving fibers, and perform photoelectric conversion to detect respective signal intensities; and an association unit configured to associate the respective signal intensities detected by the detection unit with distances from the illumination fiber to the respective light-receiving fibers on an end face of a distal end portion of the measurement probe, characterized in that the measurement probe is configured to project light having an intensity gradient that varies symmetrically around the illumination fiber to the end face of the distal end portion of the measurement probe, the association unit is configured to associate the respective signal intensities in the light-receiving fibers of the measurement probe detected by the detection unit and the distances of the respective light-receiving fibers from the illumination fiber on the end face of the distal end portion, when the light having the intensity gradient that varies symmetrically around the illumination fiber is projected to the end face of the distal end portion of the measurement probe, and the fiber bundle is configured such that an arrangement of the optical fibers on an end face of a proximal end portion and an arrangement of the optical fibers on the end face of the distal end portion are different from each other. a light source unit configured to emit light for measuring a living tissue; a measurement probe including a fiber bundle, the said fiber bundle including an illumination fiber that is configured to propagate light from the light source unit to a distal end as illumination light and illuminate the living tissue with the illumination light, and a plurality of light-receiving fibers configured to receive return light of the illumination light illumined by the illumination fiber and reflected and/or scattered at the living tissue; a detection unit configured to receive the return light of the illumination light detected by the plurality of respective light-receiving fibers, and perform photoelectric conversion to detect respective signal intensities; and an association unit configured to associate the respective signal intensities detected by the detection unit with distances from the illumination fiber to the respective light-receiving fibers on an end face of a distal end portion of the measurement probe, characterized in that the measurement probe is configured to project light having an intensity gradient that varies symmetrically around the illumination fiber to the end face of the distal end portion of the measurement probe, the association unit is configured to associate the respective signal intensities in the light-receiving fibers of the measurement probe detected by the detection unit and the distances of the respective light-receiving fibers from the illumination fiber on the end face of the distal end portion, when the light having the intensity gradient that varies symmetrically around the illumination fiber is projected to the end face of the distal end portion of the measurement probe, and the fiber bundle is configured such that an arrangement of the optical fibers on an end face of a proximal end portion and an arrangement of the optical fibers on the end face of the distal end portion are different from each other.