Speckle noise on synthetic aperture radar image is inevitable. Understanding the SAR image becomes very hard because of the existence of speckle noise, and thus the application of SAR image is influenced severely. There are many methods to restrain the speckle noise in image domain. In frequency domain, there are methods based on FFT transform and WT transform. In this paper, according to the special characteristics of SAR image of desert area, a method based on wavelet package is proposed and compared with other filter methods. The image processing results show that this method restrains the noise effectively, and the edge information of the image is also retained well.