Purge device of load port and purge method thereof

A purging device includes an intake module, an exhausting module, a first purge gas supplying module, a second purge gas supplying module, a control valve and a processing module. The processing module is electrically connected to the control valve, and is operable so as to control the control valve to allow flow of a first purge gas from the first purge gas supplying module into the intake module, while preventing flow of a second purge gas from the second purge gas supplying module into the intake module, or allow flow of the second purge gas from the second purge gas supplying module into the intake module, while preventing flow of the first purge gas from the first purge gas supplying module into the intake module.