Abstract: The aggregation domains and the texture patterns of surfactant monolayers at the air-water interface can be observed directly by Brewster angle microscopy(BAM).These images are optical outcomes which result from the deviation of molecular aggregation states and orientations from the perfect crystal structures at the surface.The information of these states and the orientations might be provided via utilizing the BAM patterns. This work investigated the combination of the arrangements and the orientations of surfactants caused by different structure defects at surface,built up the models of orientational molecules,simulated the BAM images with the help of electromagnetic theory and compared them with the(experimental) BAM images.Results show that the theoretical simulation images are consistent with the(experimental) images observed by BAM generally and the complicated BAM images can be obtained by(combining) the spot defects and the line defects.