The disclosure discloses a method for implementing data synchronization between a source database and a target database, which includes: a synchronization device acquires at least one first Logical Change Record (LCR) and a keyword of the first LCR from the source database; the synchronization device determines whether there is a second LCR with a keyword as same as the keyword of the first LCR in the synchronization device itself; the synchronization device processes the first LCR to generate a processed LCR according to the determination result, so that the synchronization device stores only one LCR containing the keyword of the first LCR; and the synchronization device sends the processed LCR to the target database. Accordingly, the disclosure also discloses a device and system for implementing data synchronization between a source database and a target database. The disclosure can reduce the data transmission load when implementing the synchronization between the source database and the target database.