Abstract: Since LED lamp can not meet the practical requirements in light distribution and heat dissipation, its power saving and economic advantages are not fully utilized. Based on the existing solar LED streetlamps, technical specification and performance requirement of 90W solar LED streetlamp are established according to relevant national standards and the industry standards, and the preliminary design is made accordingly. The major components are selected and reviewed, and a design scheme is obtained. MATLAB is used to simulate LEDs illumination profile and light distribution, light distribution and heat dissipation are optimized to meet the requirements of street light.