The changes in mammary gland bioimpedance were examined in the dynamics of the inflammatory process. Bioimpedance of affected gland was 2-3-fold lower than that of the contralateral one; normally, this difference did not exceed 10%. The phases of inflammation development were paralleled by changes in bioimpedance. During wound epithelization, impedance increased and approximated the normal level. Further increase of bioimpedance by more than 30% and its stabilization at this level attested to recurrence of inflammation, while its irreversible drop indicated devitalization the tissues. The diagnostic criterion attesting to the development of local inflammatory reaction is deviation of bioimpedance in the impaired area by more than 15% from that of the adjacent intact site.