In order to assist in identifying the magnetic attraction status of the bolster spring disassembly fixture and improve the reliability of the fixture in automatic disassembly operations, a research was conducted on the transient current response characteristics of the electromagnetic bolster spring disassembly fixture. Based on fundamental electromagnetic theory, the influence of air gap and magnetic circuit changes on the magnetic circuit reluctance, inductance, magnetic flux and electromagnetic force was mainly analyzed. By using MATLAB, the influence of magnetic circuit inductance on the dynamic response of transient current and its variation law were detailed analyzed during power-on processes. It is found that the inductance of the electromagnet is minimal (can be regarded as the inductance) when it is in no-load state, resulting in the fastest transient current response. As the inductance gradually increases (corresponding to the full-load state of the electromagnet), the response characteristics of the coil transient current gradually slow down. The response characteristics of the electromagnet's transient current are tested under different magnetic attraction conditions. The experiments reveal that when attracting the load-bearing spring, the steady-state time of the coil's transient current changes from 0.75 s under no-load conditions to 1.5 s under full-load conditions. When attracting the anti-vibration spring, the steady-state time of the coil's transient current changes from 0.85s under no-load conditions to 1.6 s under full-load conditions. Finally, theoretical analysis suggests that adding a resistor and a capacitor to the existing circuit can effectively improve the transient response characteristics of the electromagnet.