For the problem of the life of LED affecting by high temperature, a more perfect optimization designmethod is proposed. Through analyzing the factors affecting the life of LED lamps, it is pointed out that temperatureis the key factor affecting the life of LED lamps. The analysis of the reason of MOSFET serious heating is focusedon. And a feasible optimization scheme is put forward, that is, the optimization design of LED chips in series andparallel, and the experiment is carried out. The experimental results show that the temperature of MOSFET can beeffectively reduced about 10 ℃ by changing the arrangement of LED chips, which proves the feasibility of the opti.mal design.