An encoding method for a frame synchronization signal includes: encoding a predetermined intermediate variable corresponding to a cell ID or cell group ID to obtain short codes corresponding to the cell ID or cell group ID; and generating SCH codewords according to the said short codes, instead of directly encoding the cell ID or cell group ID, thereby ensuring that a first short code in each generated S-SCH codeword is larger than a second short code, or a first short code in each generated S-SCH codeword is smaller than a second short code, and a short code distance thereof is relatively small, so as to enhance the reliability of the frame synchronization. An encoding apparatus for a frame synchronization signal is further provided.