Disclosed herein are computer-implemented methods; computer-implemented systems; and non-transitory, computer-readable media, for sending cross-chain messages. One computer-implemented method includes storing an authenticable message (AM) associated with a first account of a blockchain node to a blockchain associated with the first blockchain network, where the AM comprises an identifier (ID) of the first blockchain network, information of the first account, and information of a recipient of the AM. The AM and location information is translated to a relay to be forwarded to the recipient located outside of the first blockchain network, where the location information identifies a location of the AM in the first blockchain and the recipient includes one or more accounts outside of the first blockchain network.