An optical measurement apparatus according to the present invention includes a probe having an irradiation fiber that propagates light supplied from a base end and irradiates the light from a leading end and a plurality of light receiving fibers that propagate light incident from leading ends and output the light from base ends a light source unit that generates white light to be irradiated onto the body tissue and supplies the white light to the irradiation fiber a measurement unit that performs spectrometry for returned light from the body tissue output from each of the light receiving fibers at a predetermined measurement timing and a determination unit that determines whether or not a measurement value measured by the measurement unit is equal to or smaller than a predetermined threshold value, and causes the light source unit to perform a light emission process for obtaining a characteristic value of the body tissue for a predetermined time and causes the measurement unit to perform a spectrometry process for obtaining a characteristic value of the body tissue for the predetermined time if it is determined that the measurement value measured by the measurement unit is equal to or smaller than the predetermined threshold value.