The present invention provides an apparatus and method for code group identification and frame synchronization for cell searching used in wide-band DS-CDMA cellular systems. This method characterizes each secondary synchronization code sequence (SSCS) with a corresponding theoretical frequency sequence, which represents the occurrence times of CS1 to CS16 in a corresponding SSCS. Thus, 64 secondary synchronization code sequences corresponding to 64 code groups defined in DS-CDMA systems also corresponds to 64 theoretical frequency sequences. By characterizing the SSCS transmitted by a base station, a real frequency sequence can be generated. Comparing the real frequency sequence with the 64 theoretical frequency sequences, one can determine one or two candidate code groups, which may be employed by the base station. Finally, one can compare the SSCS transmitted by the base station with all the possible SSCSs corresponding to the candidate code groups to determine a specific code group and a frame boundary for the base station.