In the confined space, heat dissipation problem is one of the factors that restrict the development of high power LED in automotive headlamps. A flat panel micro heat pipe group with copper powder as sinter core, is proposed as a radiator used in automobile LED headlamp. Under different working conditions of vehicle lights, the effects on the radiator performance of thermal resistance, ambient temperature, and convective heat transfer coefficient of the fin group are studied. Finally, the heat dissipation experiment of the micro heat pipe for vehicle light is conducted. The results show that, under normal working conditions, when the power of the LED lamp is 60 W, the junction temperature of the LED is 67 ℃, and the thermal resistance of the radiator is stable at 0.61 K/W. Under complex and high power conditions, the junction temperature of LED is below 120 ℃,and when the convective heat transfer coefficient of the fin is greater than 80 W/(m 2·K), the junction temperature of LED tends to be stable. Meanwhile, the performance of the radiator is verified by experiments. When the output power is 50 W, the LED junction temperature of the heat pipe radiator is 58 ℃, indicating that the new heat pipe radiator can meet the heat dissipation requirements of the LED headlamps.