Embodiments of the disclosure provide a system and method for adjusting an oxygen content in an FOUP. The system for adjusting the oxygen content in the FOUP includes an inflating assembly, the FOUP, a controller and a detecting assembly; the inflating assembly is connected with a gas inlet of the FOUP and configured to input an inert gas to the FOUP; the detecting assembly is connected with a gas outlet of the FOUP and configured to detect the oxygen content of the gas in the FOUP; and the inflating assembly and the detecting assembly are both connected with the controller, and the controller is configured to adjust a flow of the inert gas input from the inflating assembly to the FOUP according to the oxygen content detected by the detecting assembly.