Customer multi-institution payment method and system based on block chain

The invention discloses a customer multi-institution payment method and system based on a block chain, and relates to the field of block chains, and the method comprises the steps: enabling a block chain to store the information of a plurality of accounts of a customer, and transmitting the information of each account to a corresponding payment institution; the corresponding payment institution determines normal payment based on the account information, and returns reply information to the block chain; during payment, if the balances corresponding to the plurality of accounts are all smaller than the transaction amount, initializing the selectable accounts into a plurality of accounts, and executing the following steps: determining the selected probability of a plurality of maximum accounts in the selectable accounts according to the account partial order determined by the block chain; selecting an account from the maximum accounts according to the selected probability; performing identity authentication base