Using sapphire (Al2O3) as the substrate, the influence of the parameters of patterned substrate (PS) such as pattern choice, radius and gap of primitive cell on LED efficiency is studied by software design and simulation. The results indicate that the patterned substrate structurea hemisphere structure whose radius and gap are 1.25 μm and 0.5 μm respectively is the optimal structure. Then the LED of this kind of structure is gotten by means of wet etching, and its efficiency increases by 33% compared with normal LED. The reason why the PS technology can increase LED efficiency is analysed, which is that it can improve the chip quality and increase internal quanntum efficiency.