High-brightness LED control is required for stable operation, thus the driver and control system must be designed to deliver a constant current to optimize reliability and ensure consistent luminous flux. In this paper, the sliding mode current controller is designed to adjust the illumination density of power LEDs. The controller design model of power LEDs, including its driving circuit, is proposed to realize the dimming control of power LEDs. A buck converter is introduced to drive the power LEDs and reduce the input voltage to a lower level. The sliding mode software controller is implemented to adjust the dimming of power LEDs. The proposed strategy for driving power LEDs is investigated and comparatively studied by experiments.