Abstract: A new algorithm which can use lacunarity feature to discriminate vehicle target from natural clutter in SAR imagery is developed in this paper. Firstly, the variation and irregularity of back-scattered intensity for vehicle target and natural terrain are analyzed, which are resulted from their different scattering centers with different spatial arrangement and other cases. The vehicle image presents more irregularity and largeness of gaps than natural terrains image. Based on fractal theory, the lacunarity feature is estimated to measure the difference and can be used to eliminate the natural clutter. And then, the real X band SAR image data are applied to validate the above algorithm, and the performance of this algorithm is good.