Abstract: The existing blockchain presents a multi-chain trend. Traditional consensus algorithms do not have dynamic scalability for multi-chain, making it difficult to cope with the contradiction between open use and closed maintenance of large-scale permissioned blockchain. For this problem, a novel multi-chain consensus algorithm, MC-RHotStuff, is proposed: Nodes have different roles, including alternative nodes, candidate nodes, and consensus nodes. Each working chain has consensus nodes and alternative nodes. After the admission verification, the candidate node will become an alternative node; A consensus node has a reputation value that other nodes do not have, and a consensus node that performs the correct behavior will increase the reputation value, while a consensus node that performs the wrong behavior will deduct the reputation value, then the node with abnormal reputation value will be found through the node reputation calculation and filtering algorithm MC-Scan, and a new consensus node will be selected from the alternative nodes to exchange with the abnormal node. In addition, a dynamic node adjustment algorithm, MC-Schedule, is proposed to achieve optimization by detecting the transaction volume of each blockchain and dynamically adjusting the number of consensus nodes, which not only ensures the efficient execution of the blockchain system but also improves the speed of node filtering. MC-RHotStuff proposes a node state synchronization mechanism, MC-Syn, to ensure that the consensus operates normally when the node number change or the consensus group change. Compared with existing systems, transaction throughput and latency have been comprehensively improved by about 15%.