On the basis of analyzing the characteristic of the MARC data stored in the relation database, this paper proposes a kind of designing scheme of a MARC data mirror system. When the destination database replicats the MARC data from the source database, by introducing the file transfer server, this scheme transforms the remote operation to the local operation, changes the record synchronization into the network file transfer, and makes the replication of the MARC data between source and destination be more reliable, more effective and more applicable.