Based on expatiate wavelet transform princip le,aimed at the construction of fusion operator, a new scheme using the correlation of decomposition coefficients is presented.With mean, variance and covariance of decomposed high frequency sub-image, the matching degree and adding coefficient can be gained, and then the fusion calculation of high frequency sub-image can be completed. For low frequency sub2image, average coefficient is adop ted. Finally the fusion image is obtained by taking inverse wavelet transform. In addition, with entropy, cross entropy and mutual information, the performance of fusion scheme is evaluated and compared with other schemes. The experimental results show this fusion scheme is effective than other fusion schemes, the calculation course is simple, and has app lication value to engineering.