An all-fiber pulsed laser with narrow line width is introduced. The fiber laser consists of a pulsed fiber laser seed and a narrow line width abstraction device. The all-fiber pulsed laser seed is based on a semiconductor saturable absorber mirror (SESAM) with a 3-nm line width. Including an isolator, a coupler and a fiber Bragg grating the narrow line width abstraction device extracts narrow line width optical pulses from seed laser′s optical pulses and produces optical pulses with a 0.1-nm line width. The all-fiber, easy using, simple configuration, pulsed fiber laser can not only output narrow line width optical pulses, but also output the wide line width optical pulses from the pulsed fiber laser seed simultaneously, which greatly broadens the applications of the pulsed fiber lasers.