The invention relates to an automatic electromagnetic valve adjusting circuit and a method thereof. The automatic electromagnetic valve adjusting circuit comprises a coil K1 connected with a fuse FU1. The fuse FU1 is connected with a coil Y and a thyristor VS1. After a rectifier diode VD2 is connected with a resistor R1 and a resistor R2, the rectifier diode VD2 is connected with a resistor R3, a resistor R4 and a voltage stabilizing diode VD3. An audion VT1 is connected with the resistor R3 and connected with a capacitor C1 in parallel. A control loop of an electromagnetic valve is connected with a base electrode of the audion VT1 through a resistor R5 via a contact S1 and connected with a potentiometer R7. The potentiometer R7 is connected with the resistor R5, a resistor R6 and a capacitor C2 in series. One path of the audion VT1 is connected with the resistor R4, and the other path of the audion VT1 is connected with a trigger circuit of the thyristor VS1. A contact S2 is connected with 220VAC current and an electromagnetic valve Y. A coil K2 is connected with a controller B2 and a power source null line, and the coil K2 is connected with a +24V power source. The control loop of the circuit is completely separated from the power source and control of the electromagnetic valve, the situation that in the electromagnetic valve operation process, interference is caused to the controller due to overcurrent or reverse signals is avoided, and damage of the electromagnetic valve due to the sudden power getting or power losing is prevented.