The disclosure provides a data synchronization system, apparatus and method. A primary memory area is created at a destination end apparatus, and an incremental synchronization process is performed. A source end apparatus records a log for a write operation, including operation information and a sequence number for the operation. A latest destination-end write operation sequence number is recorded. The source end pushes in real-time write operation information corresponding to a source-end write operation sequence number greater than the latest destination-end sequence number to the destination end if a latest source-end write operation sequence number is greater than the latest destination-end sequence number. The destination end apparatus performs a write operation on the primary memory area according to the write operation information, records a write operation sequence number of the primary memory area and sends a latest write operation sequence number of the primary memory area to the source end apparatus.