A visceral fat determining device is disclosed which can be used easily at home for example and can obtain information on visceral fat. The visceral fat determining device comprises input means for inputting personal data that represents vital characteristics of the patient; a data processing unit capable of performing various calculations; and a display device capable of displaying the personal data and results of the calculations. Upon inputting of a waist size which is a girth of the trunk of the patient, and a hip size which is a girth of the buttocks of the patient, quantitative information on abdominal visceral fat of the patient is given through a calculation based on WHR which is a ratio of the waist size to the hip size (waist size/hip size).