To provide an element density measurement device capable of suppressing reduction of measurement accuracy due to moisture content change of a human body, when measuring glucose content in a body by an optoacoustic method.SOLUTION: An element density measurement device comprises: a light radiation part 101 for radiating a pulse-state beam light 121 having wavelength which is absorbed to glucose to a measurement part 151; and a detection part 102 for detecting an optoacoustic signal generated from the measurement part 151 to which the beam light 121 emitted from the light radiation part 101 is radiated. The element density measurement device comprises: a moisture content measurement part 103 for measuring a moisture content on a skin on the measurement part 151; and a correction part 104 for correcting the optoacoustic signal detected by the detection part 102 by the moisture content measured by the moisture content measurement part 103.SELECTED DRAWING: Figure 1【課題】光音響法による人体内のグルコースの測定における、人体の水分変化による測定精度の低下を抑制する。【解決手段】グルコースが吸収する波長のパルス状のビーム光121を測定部位151に照射する光照射部101と、光照射部101から出射されたビーム光121を照射した測定部位151から発生する光音響信号を検出する検出部102とを備える。また、測定部位151における皮膚の水分量を測定する水分測定部103と、水分測定部103が測定した水分量により検出部102が検出した音響信号を補正する補正部104とを備える。【選択図】 図1