A speckle imaging model for impulse coherent laser radar(ICLR) is derived, which proves the presence of multiplicative noise in images of ICLR. According to its statistical property, a parallel weighted average multidirectional morphological filtering algorithm is presented. Simulation result shows the algorithm can not only effectively suppress speckle noise in images but also preserve the geometrical features of images. Through comparison, it is proved that the algorithm is superior to F. Safa algorithm.