An automotive lighting with automatic brightness adjustment includes a radiator, a light source baseplate in the radiator, a LED lamp on the light source baseplate, a temperature sensor on the light source baseplate and on a side of the LED lamp, a driving power circuit board electrically connected to the LED lamp and the temperature sensor, and a driving IC on the driving power circuit board and electrically connected to the LED lamp and the temperature sensor through the driving power circuit board. The radiator has a light transmission part corresponding to the LED lamp. The driving IC of the present application adjusts the brightness of the LED lamp through the temperature sensor sensing a temperature of the environment where the LED lamp is located.