The experimental study of an Yb~(3+)-doped fiber ring laser producing ultrashort pulses is reported.The Yb~(3+)-doped fiber ring laser is found to oscillate in a mode-locked state by adjusting the polarization controller(PC) and reducing the loss in the cavity.By changing the pump power,the laser operates in either a Qswitched and mode-locked state or a mode-locked state.The central wavelength of the Q-switched and mode-locked state is 1 051 nm,and the spectral width is 11.5 nm.The central wavelength of the mode-locked state is 1 051 nm,the spectral width is 13.8 nm,and the repetition rate is 19 MHz.The paper also presents some preliminary analyses on the experimental results.