A method for initializing a peripheral component interconnect express (PCI-E) interface card is provided. The method includes: initializing, by a processing unit in a boot procedure according to a preset first value of a flag, a PCI-E interface card inserted in a PCI-E interface slot by using a first initialization parameter included in a basic input/output system (BIOS) code; setting, by the processing unit in the boot procedure according to the initialized PCI-E interface card, the flag to have the first value or a second value; determining, by the processing unit in the boot procedure, whether the initialized PCI-E interface card needs to be reinitialized; and reinitializing, by the processing unit according to the second value of the set flag when the PCI-E interface card needs to be reinitialized, the PCI-E interface card by using a second initialization parameter included in the BIOS code.