The invention discloses a bilayer sliced high-efficiency block chain consensus mechanism and a working method thereof. The consensus mechanism is based on a bilayer gossip topology network, and comprises a full node, a local full node, a light node and a micro node, wherein the full node is in charge of node topology and slice maintenance and is elected and updated through a full node maintenancemechanism; and the local full node is elected and updated through a local full node maintenance mechanism and is in charge of transaction validation, transaction consensus, transaction storage and account synchronization. The invention also provides a working method for the consensus mechanism. A credible and incentive node joining and updating mechanism is provided, the stability, the bandwidth capability and the computing capability of the full node and the local full node are ensured, and the impacts on a transaction confirmation speed are reduced. The consensus mechanism proposed by the invention forms a divide-and-conquer distributed account system by means of intra-slice autonomy and inter-slice collaboration to ensure to consider decentralization, scalability and security.