Simulation has been used to predict the aerial images for masks with defect free multilayer and with defect in multilayer. Mask defects are easily produced in extreme ultraviolet lithography mask fabrication process because 40 Mo/Si multilayer films are stacked and each stack is made from 2 to 4 nm. In this case, multilayer can be stacked with defects and with slightly different heights. It is hard to achieve an aerial image which we want to get. This paper discusses various image properties when there are no defects and when there are different kinds of defects on multilayer. The results were calculated by using SOLID-EUV of Simga-C. The aerial images caused by defects on the multilayer are characterized.