An induction heating fusing device and an image forming apparatuses that may control even a very small current region by tracking a resonance frequency to perform PWM control and phase control without considering a deviation of a part constant or a temperature change are provided. The induction heating fusing device includes: a serial resonance circuit having an induction coil and a condenser; a phase comparator, a phase controller, a resonance frequency tracking oscillator, and a PWM (pulse width modulation) signal generator. The phase comparator compares a phase of a pulse outputted by the PWM signal generator with a phase of current flowing through the induction coil, outputs a comparison result obtained by the comparing to the phase controller when controlling the phase, and outputs the comparison result to the resonance frequency tracking oscillator when performing PWM control.