Abstract: Different from the light distribution characteristics of the traditional light source, LED light characteristics are more complex, the second optical design for LED used in automotive lighting needs to be done. According to the light distribution characteristics of LED automobile headlamp, a freeform optical lens design method for LED headlamp was presented in this paper. By establishing one-to-one relationship between the coordinates of point on the receiving surface and the coordinates of point on the freeform surface of lens according to energy conservation principle, determining the mapping relationship between the energy and the lens, and applying the illumination optimization method, the coordinates of point on the freeform surface of lens was solved out with numerical methods based on non-imaging optics theory, then modeling software was used to establish an optical model for the freeform optical lens. Through tracing the light with Monte Carlo simulation method, the final effect of light distribution fully meets the Automotive headlamps with LED light sources and/or LED modules (GB25991-2010) standards. The simulation results show that the optical efficiency is improved greatly and can be up to 91%.