Using a 248 nm KeF excimer laser as the UV light source,the inscription method of fiber Bragg grating (FBG) on large-mode-area double-clad fiber (LMA-DCF) was studied with phase mask technique.The center wavelength of the fabricated FBG was at 1076.11 nm with a 3 dB bandwidth of 0.32 nm and reflectivity of 99.9% in the fundamental mode.The FBG was then applied to a Yb³⁺-doped double-clad fiber laser as a highly reflective cavity mirror.The 144 W of stable output power with a slope efficiency of 60% was achieved.The spectral characteristics of the output laser matched well with that of the FBG and an excellent Gaussian beam shape was achieved.