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‐&mgr;m‐wide, 500‐&mgr;m‐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.