Disclosed is a bi-directional wavelength division multiplexing self-healing passive optical network including: a central office for multiplexing and transmitting downstream optical signals to a first and a second main fiber; a remote node connected to the central office through the first and the second main fiber, for transmitting multiple pairs of the downstream optical signals, which are obtained by demultiplexing one inputted pair of the multiplexed downstream optical signals according to wavelengths, to corresponding pairs of distribution fibers; and a plurality of optical network units connected to the remote node through the multiple pairs of distribution fibers, each of the optical network units being selectively connected to one corresponding pair of the distribution fibers, for receiving a corresponding downstream optical signal from the selected distribution fiber.