We report on high-power AlGaAs/GaAs graded-index single quantum well surface-emitting lasers (SELs), with etched vertical mirrors and integrated 45°beam deflectors fabricated by a tilted ion beam etching technique. 100-μm-wide, 500-μm-long, broad-area SELs exhibited a threshold current of 300 mA, a peak power of more than 380 mW, and an external differential quantum efficiency of 17% without facet coating. The SELs showed stable operation up to 7th. These results show the highest power and external differential quantum efficiency reported to date for 45°beam deflecting SELs. The full widths at half maximum of the surface-emitting far-field pattern parallel and perpendicular to the laser axis were 8.5°and 14°, respectively.