This paper designs a precise control drive circuit for LED high power lamp. It takes the STC89C52 single chip microcom- puter chip as the control core, selects the PT4115 as the LED power supply chip, uses the PWM to adjust the brightness mode, and re- alizes the adjustment of brightness. The LED has good characteristic of constant current, little change of light color. The circuit can be controlled by key or infrared light, and provides over-voltage and over-current protection. Through experiments, the circuit has good stability and can be adjusted by software program, which can realize multi-stage and even stepless dimming and achieve accurate dim- ming.