We demonstrate an individually-switchable multi-wavelength fiber ring laser using semiconductor optical amplifier with novel switchable band-pass filters. The switchable band-pass filter is based on a fiber Sagnac loop interferometer incorporating both fiber Bragg gratings and polarization controller. The proposed multi-wavelength fiber ring laser shows a high output performance of independent switching at arbitrary lasing wavelength and high extinction ratio for wavelength-division multiplexing source. (c) 2007 Optical Society of America.