Introduce the principle and implementation method of C/A code replication, propose the general design idea and gives the working timing diagram. It expounds the way to implement the GPS C/A code replicator, then simulation and analysis is done. The analysis shows that it can generate exact GPS C/A code according to C/A code phase shift and GPS PRN number. The research makes certain reference basis for the related research of GPS C/A code synchronization, P code and satellite communications.