The invention discloses a fault detection method of an induction cooker synchronization circuit. The fault detection method comprises the steps of: connecting a heating wire coil, measuring an output end of a second pin of a comparator LM339, indicating that the output end is normal if the voltage to ground thereof is +4.8 V, if the voltage is low, measuring an inverting input end of the fourth pin of the comparator LM339, and indicating that the inverting input end is normal if the voltage to ground thereof is+3.7 V; when the voltage is low, indicating that a filtering capacitor C2, 5 uf/275 V fails and a resistor R23 (330 K/2 W) changes a value and is damaged, measuring a non-inverting input end of a fifth pin of the comparator LM339, and indicating that the non-inverting input end is normal if the voltage to ground thereof is +3.8 V; when the voltage is low, indicating that resistors R24 (240 K/2 W) and R27 (240 K/2 W) change values, form open circuits and are damaged, a capacitor C19 leaks, a voltage-stabilizing diode Z3 is broken down, and a PAN-IRO output voltage of a ninth pin of a CPU chip has a ground fault and is damaged, resulting in a low voltage to ground of an output end of a second pin of the LM339, and replacing damaged elements.