Method and device for monitoring and supplementing light

The invention discloses a method and a device for monitoring and supplementing light. A light supplementing source of monitoring equipment comprises at least two groups of sub-light sources with different illuminating angles. The method comprises the following steps of: acquiring a distance between the monitoring equipment and a target object and the multiplying power of the monitoring equipment; and starting the sub-light source matched with the distance and the multiplying power to supplement light according to preset conditions. By selecting the sub-light sources from the light supplementing source in reference to the multiplying power of the monitoring equipment and the distance between the monitoring equipment and the target object comprehensively, after the light supplementing source is matched with the monitoring equipment, the light supplemented to pictures monitored by the monitoring equipment is moderate, and the images are clear all the time.