A communication recovering system for a wavelength division multiplexed passive optical network (WDM PON) includes a central office and remote nodes. When there is a fault in an optical fiber connecting a first blue/red band coupler to a blue/red band coupler R11, optical signals are inputted/outputted thereto/therefrom through a first 1×2 optical switch and a second blue/red band coupler, and when there is a fault in an optical fiber connecting the second blue/red band coupler to a blue/red band coupler R21, optical signals are inputted/outputted thereto/therefrom through the second 1×2 optical switch and the first blue/red band coupler.