The patterned sapphire s ubstrate (PSS) is used as a fundamental technology to overcome the material stre ss which results from a combination of lattice mismatch and thermal expansion coefficient mismatch and it can improve the light extraction e fficiency for GaN-based light-emitting diodes (LEDs).In order to investigate the effect of PSS′s morp hology on the emission properties of GaN LEDs,the LEDs with the same structures were fabricat ed on hemispherical and triangular pyramidal PSSs by controlling the fabricating process and parameters. The measurement results of emission properties of the TPSS-LED show that the light output power for PSS -LEDs would be enhanced as the fill factor of PSS increases.Then,compared with TPSS,the optical properties of HPSS are superior when they have the same fill factor.We′ve come to the conc lusion that the increase of the fill factor can make the light output power increase,and by optimizing the structure of the PSS, the light extraction efficiency could be increased as the light path in LEDs cou ld be improved.