Embodiments of the present invention provide a frame synchronization method. The frame synchronization method of the wireless system includes: separately delaying a signal received from one of N receiving antennas in K tributaries, and outputting K delayed signals, where N and K are positive integers; generating a first output signal by performing a correlation operation on the K delayed signals and a preamble subsequence; generating a second output signal by performing the correlation operation on each of the K delayed signals and each of the K delayed signals itself; and performing cancellation processing for the first output signal and the second output signal to obtain a string of data stream, obtaining a maximum value of the string of data stream as a correlation peak, so as to determine a position of a frame header according to a time point corresponding to the correlation peak.