In this study a working lamp used on the off-road working machines and vehicles is designed by using the LED diodes instead of a halogen bulb. In the design, firstly a LED array is determined and a proper driver circuit that can provide the required optical power is designed, and the working lamp developed is tested under various conditions. The luminous output values of the designed LED working lamp are compared with those of a commercial working lamp, which uses a halogen bulb. It is evaluated that in automotive applications lamps using LEDs could be successfully utilized depending on the optical efficacy of the LED used, the designs of the LED driver and the reflector.