Abstract: Since preamble-based channel estimation method can overcome the intrinsic inter-symbol interference and inter-carrier interference in OFDM/Offset QAM (OFDM/OQAM) system, it becomes the commonly used structure in similar systems. In this paper, according to the pilot structure and the characteristic of OFDM/ OQAM signal, the correlation between the adjacent sub-carriers is analyzed, and in turn an improved channel estimation algorithm is proposed. Through calculating the correlation coefficient between the adjacent subcarriers, weighting operation is carried out in frequency domain to reduce the effect of interference and noise on channel estimation. Analysis and simulation results demonstrate that this algorithm can effectively improve both channel estimation accuracy and system performances of traditional ones.