A novel narrow line-width Erbium/Ytterbium (Er/Yb) co-doped double-clad fiber ring laser has been reported. To obtain higher output power,the laser is pumped by six Continuous Wave Laser Diodes (LD) operating at 976 nm through six pigtails of a Tapered Fiber Bundle connected with the Er/Yb codoped fiber. By using fiber Bragg grating (FBG) Sagnac loop mirror as a wavelength-selective device,the cladding-pumped fiber laser oscillation with a line-width of 0.06 nm and central wavelength of 1548.11 nm has been obtained. By using the saturable absorption of an un-pumped Er/Yb co-doped double-clad fiber,with different pump power,such laser can operate at different modes. The self-Q-switched pulse with pulse width of 2.8 μs,period of 20 μs and average power of 38.4 mW can be achieved at the pump power of 719 mW. And the peak power of the Self-Q-switching pulse is 274.3 mW. When the pump power is 3.6 W,the maximum peak power of the self-mode-locked pulse reaches 10 W with a repetition rate of 7.937 MHz and duration of 4ns. As no active element is inside the cavity,this fiber ring laser potentially has many advantages over conventional pulsed fiber laser systems.