PROBLEM TO BE SOLVED: To provide an electronic thermometer and a body temperature-measuring method which can measure an accurate deep body temperature.SOLUTION: An electronic thermometer 2 includes: first body surface temperature-measuring means 20A； first reference temperature measuring means 24A； second body surface temperature measuring means 20B； second reference temperature measuring means 24B； third temperature measuring means 20C, 20D, and 20E which measure a third temperature which is different from measurement positions of first body surface temperature and second body surface temperature； temperature correction means 40 for correcting the first body surface temperature, first reference temperature, second body surface temperature, and second reference temperature, by using the third temperature； and deep body temperature calculation means 42 for calculating a deep body temperature of a subject using the first body surface temperature, first reference temperature, second body surface temperature, and second reference temperature corrected by the temperature correction means 40.
