The invention provides a lighthouse monitoring system and method and relates to the technical field of monitoring. The system comprises a light detector, a master control circuit and a fault detectioncircuit. The light detector is set in an environment where a lighthouse is. The light detector detects external light in the environment where the lighthouse is and triggers the master control circuit to disconnect connection between a power supply and the lighthouse when detecting that the external light luminance reaches a threshold, so the power supply stops supplying power to the lighthouse.When the light detector detects that the external light luminance does not reach the threshold, the light detector triggers the master control loop to carry out the connection between the power supplyand the lighthouse, so the power supply supplies the power to the lighthouse, and the fault detection circuit is triggered to work. The fault detection circuit monitors whether the lighthouse is lighted or not. When the lighthouse is not lighted, prompt is carried out. Through utilization of the lighthouse monitoring system and method, the reliable monitoring can be carried out on the lighthouse.