Intelligent street lamp reduces the effective current of light source by adjusting the output voltage of lighting circuit. In the initial stage of linear voltage drop, the illuminance drop is not obvious, but the power saving decreases according to the square of voltage. Intelligent street lamp has the characteristics of high luminous efficiency, low power consumption, long service life, safety and reliability, high light output rate of light source and environmental protection. It is suitable for urban main roads, urban secondary roads, industrial parks, urban and rural roads and other fields.