A new LED rear light for automotives is proposed and demonstrated for EU ECE R07 regulation. The full rear light is a combination of a position lamp and a braking lamp, and LED light bars and micro-prisms are involved as their essential components. The micro-prisms are applied to homogenize the output of the rear light to decrease glare and accomplish EU ECE standard. Through experiments, it is shown that EU ECE R07 regulation can be met in the proposed rear light, and 12% (position lamps) and 26.5% (braking lamps) higher candela can be enhanced after the optimization of micro-prisms.