In order to provide a heat treatment apparatus and method for induction tempering through temperature control, the induction heat treatment apparatus of the present invention conducts tempering through high-frequency heating of a workpiece (1), and includes temperature control means for adjusting the temperature of the heating workpiece (1). The temperature control means includes heating means (2) for high-frequency heating a workpiece (1), temperature-control-dedicated temperature measuring means (3) for measuring the temperature of the workpiece (1) heated by the heating means (2), and temperature adjusting means connected to the temperature measuring means (3) for providing a temperature control signal to the heating means (2) based on temperature information from the temperature measuring means (3). Further, the induction heat treatment apparatus preferably includes tempering control means, including tempering-dedicated temperature measuring means (5) for measuring the tempering temperature of the workpiece (1) heated by the heating means (2), and tempering time adjusting means (6) connected to this temperature measuring means (5) for adjusting the tempering time based on temperature information from the temperature measuring means (5).