Abstract: The present invention discloses a blockchain system comprising N local area chains and M master nodes, N is an integer greater than or equal to 2, and M is an integer greater than or equal to 1; a first local area chain includes at least one child node and a first master node, both connection between the at least one child node and connection between the at least one child node and the first master node are established, the first local area chain is any one of the N local area chains, and the first master node is one of the M master nodes; and internal shared information of the first local area chain is shared between the at least one child node, and external shared information is shared with other local area chains in the N local area chains through the first master node and other master nodes.