A method for upgrading a blockchain system, comprising steps of: determining a first target support version number of the blockchain system, after an initial binary program is updated to a target binary program by participant nodes in the blockchain system; determining a first target upgrade version number shared by the participant nodes in the blockchain system according to the first target support version number; and upgrading a system version of an initial operation version number currently operated on the blockchain system to a system version of the first target upgrade version number, when a voting result of the participant nodes on a system upgrade proposal transaction is passed; wherein the upgrade proposal transaction is initiated by a chain-level administrator account, the system version of the first target support version number is a system version compatible with the target binary program, the first target support version number is a set of version numbers of support versions corresponding to the participant nodes in the blockchain system, and comprises the initial operation version number and the first target upgrade version number, the first target upgrade version number is higher than the initial operation version number, and the participant nodes are nodes participating in a consensus mechanism in the blockchain system; wherein, before the step of upgrading the system version of the initial operation version number currently operating on the blockchain system to the system version of the first target upgrade version number, the method further comprises steps of: clearing the first target upgrade version number recorded in the ledger of the blockchain system if a new node is added in the blockchain system; re-determining a second target support version number of the blockchain system in which the new node is added; calculating a second target upgrade version number of the blockchain system according to the second target support version number, and recording the second target upgrade version number in the ledger; and upgrading, when the voting result of the system upgrade proposal transaction re-initiated by the participant nodes to the chain-level administrator account is passed, the system version of the initial operation version number currently operating on the blockchain system to the system version of the second target upgrade version number. determining a first target support version number of the blockchain system, after an initial binary program is updated to a target binary program by participant nodes in the blockchain system; determining a first target upgrade version number shared by the participant nodes in the blockchain system according to the first target support version number; and upgrading a system version of an initial operation version number currently operated on the blockchain system to a system version of the first target upgrade version number, when a voting result of the participant nodes on a system upgrade proposal transaction is passed; wherein the upgrade proposal transaction is initiated by a chain-level administrator account, the system version of the first target support version number is a system version compatible with the target binary program, the first target support version number is a set of version numbers of support versions corresponding to the participant nodes in the blockchain system, and comprises the initial operation version number and the first target upgrade version number, the first target upgrade version number is higher than the initial operation version number, and the participant nodes are nodes participating in a consensus mechanism in the blockchain system; wherein, before the step of upgrading the system version of the initial operation version number currently operating on the blockchain system to the system version of the first target upgrade version number, the method further comprises steps of: clearing the first target upgrade version number recorded in the ledger of the blockchain system if a new node is added in the blockchain system; re-determining a second target support version number of the blockchain system in which the new node is added; calculating a second target upgrade version number of the blockchain system according to the second target support version number, and recording the second target upgrade version number in the ledger; and upgrading, when the voting result of the system upgrade proposal transaction re-initiated by the participant nodes to the chain-level administrator account is passed, the system version of the initial operation version number currently operating on the blockchain system to the system version of the second target upgrade version number. clearing the first target upgrade version number recorded in the ledger of the blockchain system if a new node is added in the blockchain system; re-determining a second target support version number of the blockchain system in which the new node is added; calculating a second target upgrade version number of the blockchain system according to the second target support version number, and recording the second target upgrade version number in the ledger; and upgrading, when the voting result of the system upgrade proposal transaction re-initiated by the participant nodes to the chain-level administrator account is passed, the system version of the initial operation version number currently operating on the blockchain system to the system version of the second target upgrade version number.