A single-mode-quasi-continuous-wave 980 nm Yb-doped fiber laser is realized. An acousto-optics Q-switched Nd:YAG laser at 946 nm is used as pump source and the high Yb-doped single-mode fiber is used as gain medium. The total average power of the laser pulse is 73 mW at 980 nm when the pulse duration is 10 ns at the repetition frequency of 16 kHz. The quasi-continuous-wave 980 nm fiber laser oscillator used as seed source is amplified by another 28 cm Yb-doped fiber. As a result,the pulse with average output power of 167 mW is generated. The pulse width is 15 ns with the peak power of 700 W.