A body fat measuring device includes at least one pair of first electrodes to be disposed respectively at a first site and a second site sandwiching the abdomen of a subject, and an electrode group including a first abdomen electrode to be disposed at a surface of the abdomen of the subject. The first abdomen electrode includes a pair of second electrodes and a pair of third electrodes disposed in an alignment direction substantially perpendicular to a cross section of the abdomen. In a case where electric current is applied via the first electrodes, a first potential difference between electrodes of one predetermined pair included in the first abdomen electrode is detected (S12). In a case where electric current is applied the third electrodes, a second potential difference between the second electrodes is detected (S20, 28, 36, 44). Based on the detected two types of potential differences and physical data of the subject, the visceral fat amount of the subject is calculated (S48).