A method, circuit and apparatus for protecting power supply of a peripheral component interconnect express (PCIE) card, and a medium are provided, card hardware design. When the PCIE card is not completely inserted into a slot of a server, a first power supply and a second power supply are controlled to release electric energy, a controller is controlled; to turn off a first MOS transistor, and a load is charged with the electric energy released by the second power supply. When the PCIE card is completely inserted into the slot of the server, a PRSNT #signal is generated, a second MOS transistor is controlled to be turned on, and the controller is controlled to turn on the first MOS transistor. When the PCIE card is not completely pulled out, the second MOS transistor is controlled to be turned off, and the controller is controlled to turn off the first MOS transistor.