We present an all-fiber dual-wavelength holmium-doped fiber laser operating in 2 μm region using a newly developed holmium-doped fiber(HDF) as a gain medium.The proposed fiber laser is constructed by using a hybrid gain medium,i.e.,a thulium-ytterbium co-doped fiber(TYDF) and an HDF in conjunction with a simple half-opened linear cavity,which is formed by a broadband mirror and an output coupler reflector.Without the HDF,the TYDF laser operates at wavelengths of 1991 and 1999 nm with a signal-to-noise ratio of more than 34 dB and the slope efficiency of 26.16%.With the HDF,dual-wavelength output lines are obtained at 2075 and 2083 nm with signal-to-noise ratios of more than 17 dB,3dB bandwidth of less than 0.2 nm and the power difference between the two peaks of less than 1 dB at the TYDF laser pump power of 320 mW. We present an all-fiber dual-wavelength holmium-doped fiber laser operating in 2 μm region using a newly developed holmium-doped fiber (HDF) as a gain medium. The proposed fiber laser is constructed by using a hybrid gain medium, ie, a thulium-ytterbium co-doped fiber (TYDF) and an HDF in conjunction with a simple half-opened linear cavity, which is formed by a broadband mirror and an output coupler reflector. Top of the HDF, the TYDF laser operation of wavelengths of 1991 and 1999 nm with a signal-to-noise ratio of more than 34 dB and the slope efficiency of 26.16% .With the HDF, dual-wavelength output lines are obtained at 2075 and 2083 nm with signal-to-noise ratios of more than than 17 dB, 3dB bandwidth of less than 0.2 nm and the power difference between the two peaks of less than 1 dB at the TYDF laser pump power of 320 mW.