An electrical impedance measuring apparatus includes: a plurality of electrodes adhered to a periphery of a chest of a living body; a potential measurer configured to perform a process of applying a current to any ones of the electrodes, and measuring potentials by means of other electrodes; an impedance acquirer, based on the applied current and the potentials obtained by the potential measurer, configured to obtain information related to an impedance of each of meshes, a chest section divided into the meshes; and an average value calculator configured to obtain a whole-region average value of impedances of all meshes of the chest section, and configured to obtain an ROI average value of impedances of meshes contained in each of ROIs, a whole region of the chest section segmented into the ROIs.