Provided is a data synchronization apparatus. The data synchronization apparatus includes a signal conversion block converting individual serial digital signals into parallel digital signals in response to a load signal and converting the parallel digital signals into synchronized serial digital signals in response to a synchronization load signal which does not overlap the load signal, a clock/load signal generator outputting a reference load signal for generating the synchronization load signal to the signal conversion block, a multiplexer multiplexing the synchronized serial digital signals, and a first serial-to-parallel (S/P) converting the multiplexed signal into parallel signals.