A PCIe switch working mode updating method and apparatus, an electronic device, and a computer-readable storage medium, which are applied to a controller. The PCIe switch working mode updating method includes: determining a required switch firmware version of a system according to system configuration information; determining the current switch firmware version according to the current port definition state of a PCIe switch; determining, according to the required switch firmware version and the current switch firmware version, whether a switch port reallocation operation needs to be executed; and under the condition that the switch port reallocation operation needs to be executed, sending, to the PCIe switch, a data file corresponding to the required switch firmware version, so that the PCIe switch updates a working mode according to the data file.