The invention relates to a distributed layered protection system and method for a power distribution network containing a microgrid group, and a method. The system comprises an equipment protection layer, a microgrid protection layer and a power distribution network protection layer. The method comprises the steps: employing three-layer protection for the power distribution network containing themicrogrid group according to a protection range and the difference of different protection objects: equipment-level protection, microgrid-level protection and power distribution network level protection; taking the equipment-level protection as the main protection when a distributed power supply has a fault, and taking the microgrid-level protection and power distribution network level protectionas the backup protection; taking the microgrid-level protection as the main protection when a fault happens to a microgrid, and taking the microgrid-level protection and the power distribution networklevel protection as the backup protection; taking the power distribution network level protection as the main protection when a fault happens to the power distribution network, and taking the power distribution network level protection at the upper level for the power supply of a current power distribution network as the backup protection. The system and method provided by the invention can effectively simplify the protection process, improve the adaptability, and facilitate the improvement of quickness and reliability of the protection system.