An all-fiber linear-polarization laser oscillator of high polarization extinction ratio (PER) is reported. The resonant cavity of the oscillator consists of a Yb-doped polarization-maintaining fiber as well as a pair of FBGs matched with the gain fiber in size. The high-order mode and the polarization mode along the fast axis of the polarization-maintaining fiber is suppressed because of the bend loss, which leads to a linear-polarization laser with high PER of more than 15 dB . The oscillator operates at the center wavelength of 1080 nm with a full width at half maximum (FWHM) about 1.2 nm. The highest output power of 93.2 W is obtained. Increasing pump power may improve output power further.