A spectrometry device according to an aspect of the present invention is including a light source (101), a lens 104 concentrating a light beam from the light source (101) on a reference sample (120), an objective lens (106) concentrating a light beam that has passed through the first lens (104) on a measurement sample (121), a spectroscope (109) dispersing light having a different wavelength from that of the light beam generated in the measurement sample (121) and the reference sample (120) by irradiation of the light beam into a spectrum, a detector (110) detecting light that is dispersed by the spectroscope (109), and a beam splitter (103) separating an optical path of light from the reference sample (120) and the measurement sample (121) toward the spectroscope (109) from an optical path of a light beam that propagates from the light source (101) toward the measurement sample (121).