Based on the analysis of energy loss in a laser diode, we optimize the structure of the laser diode and metal organic chemical vapor deposition (MOCVD) growth condition. By low pressure (LP) MOCVD, GaAsP/GaInP/AlGaInP strained quantum well large optical cavity structure is grown, and high power continuous wave (CW) 808 nm laser diode is fabricated. At 25 ℃ under CW operation condition, an output power of 11.5 W is obtained at 10 A current, with the threshold current being 1.15 A. The wall-plug efficiency reaches 62%. With the operation current of 5.5 A at 40 ℃, less than 2% output power degenerates over 1000 h.