In order to quickly and accurately synchronize the Orthogonal Frequency Division Multiplexing (OFDM)system, this paper mainly analyzes and studies the timing synchronization method based on the training sequence, and proposes a Carrier Frequency Offset (CFO) synchronization scheme using the pilot structure, and the whole scheme implements two modes: coarse estimation and fine estimation, in the coarse estimation, a wide range of CFO including Integer Carrier Frequency Offset(IFO) is estimated, in the detailed estimation, only fine CFO estimation is performed, and the relevant peaks obtained during timing synchronization are used for frequency offset estimation; Secondly, the quadratic interpolation algorithm is used as the frequency offset estimation algorithm, which is superior to the fast Fourier transform (FFT) algorithm. Theoretical analysis and simulation results show that under Gaussian channel and Rayleigh channel, the timing estimation and frequency offset estimation of the improved algorithm have lower mean squared error, and the range of integer and fractional frequency offset estimation is expanded, which reduces the computational complexity of the system, and the algorithm is better than the FFT algorithm,