To suppress effects due to the moisture content of a measurement object when measuring a component concentration using dielectric spectroscopy.SOLUTION: A component concentration measuring device comprises: a dielectric spectroscopic unit 2 for irradiating a measurement object with an electromagnetic wave and acquiring a complex dielectric spectroscopic spectrum； a signal processing unit 3 for normalizing an imaginary part or imaginary spectrum of complex dielectric constant in frequencies other than the frequency of an isosbestic point using the imaginary part of complex dielectric constant at the frequency of isosbestic point of the measurement object out of the complex dielectric spectroscopic spectrum； and a computation unit 4 for applying a calibration model previously created from the imaginary part or imaginary spectrum of complex dielectric constant of a sample having a known component concentration to the imaginary part or imaginary spectrum of complex dielectric constant normalized by the signal processing unit and calculating the component concentration of the measurement object.SELECTED DRAWING: Figure 1【課題】誘電分光を用いて成分濃度の測定をする際の測定対象の水分含有率による影響を抑制する。【解決手段】成分濃度測定装置は、測定対象に電磁波を照射して複素誘電率スペクトルを取得する誘電分光部２と、複素誘電率スペクトルのうち、測定対象の等吸収点の周波数における複素誘電率の虚部を用いて、等吸収点の周波数以外の周波数における複素誘電率の虚部または虚部スペクトルを規格化する信号処理部３と、成分濃度が既知のサンプルの複素誘電率の虚部または虚部スペクトルから予め作成された検量モデルを、信号処理部によって規格化された複素誘電率の虚部または虚部スペクトルに適用して、測定対象の成分濃度を算出する演算部４とを備える。【選択図】 図１
