A novel multi wavelength erbium-doped fiber ring laser is presented, which employs a novel comb filter based on a fiber Bragg grating asymetriclly written in a Sagnac interferometer. The filter has advantageous of simple design and fabrication, low cost and low insertion loss. Stable triple-wavelength and dual-wavelength laser operations with wavelength spaces of 0.34 nm and 0.5 nm, respectively, and output power differences of <2 dB and <0.4 dB, respectively, have been demonstrated.