Starting from the difficulties in the design and debugging of series switch regulated power supplies.the main reasons are analyzed to be the relatively complex circuit structure, students’ lack of thoroughunderstanding of circuit principles, and lack of experience in complex circuit debugging.In response to thisissue, a gradient progressive debugging scheme was developed using methods such as module decompositionand alternative solutions, which improved the design completion.The complete debugging process was simulatedand demonstrated using the Multisim software , demonstrating effective methods for circuit debugging and fault troubles hooting, which enriched practical guidance cases for switching power supplies.