The invention discloses a method for automatically adjusting option values of a BIOS. The specific realization process comprises following steps of setting corresponding codes in a server system which matches with an NVME (Non-Volatile Memory Express) interface; modifying a current mode into an X4X4X4X4 mode if an NVME device is connected with the NVME interface and the current mode is not the X4X4X4X4 mode when it is detected that a device accesses the NVME interface; modifying the current mode into an X16 mode if a non-NVME device is connected with the NVME interface and the current mode is not the X16 mode; and then restarting. Compared with the prior art, the method for automatically adjusting option values of the BIOS has the advantages that bandwidths are modified according to the codes, therefore, the defect that different BIOSs need to be matched when the configurations of a same product are different is avoided; the pressure of a production line is mitigated; the BIOS is unnecessarily replaced; and the BIOS of the product can be controlled and upgraded conveniently. The method is also applicable to a condition that the bandwidths need to be slotted again when the BIOS matches with other boards. The method is high in universality and practicability and is easy to realize and popularize.