Masonry structures constitute a large percentage of the current buildings in most countries around the world. The recent earthquake in different countries of the world, such as those in Iran (2003), Algeria (2003), India (2001), Turkey (1999) have shown, particularly masonry walls were damaged. Thus, masonry walls are the most vulnerable elements of buildings when subjected to earthquake loading. Therefore, it is necessary to find practical solutions by study the behavior of these walls, first without and then with retrofitting under monotonic loading. Recent earthquakes have clearly demonstrated that the development of effective and affordable strategies for the strengthening of masonry is urgently needed. As a response to these challenges, fiber-reinforced polymer (FRP) composites may offer technically and economically viable solutions. Studies on the use of fiber-reinforced polymers (FRP) as strengthening materials of masonry walls have been numerous. In this study, a variety of modeling methods are briefly described and a fast and efficient method is presented for solving the finite element masonry walls. The model used in this study is Concrete Damage Plasticity in ABAQUS software. This model is one of the macro-modeling techniques in masonry modeling. Macro models assuming homogeneity of isotopic material due to its simplicity and saving time for solution are important. In addition to the modeling of unreinforced masonry walls (URM), cohesive elements are used for modeling the behavior of masonry walls strengthened with FRP composite strips. The results showed acceptable coincidence between modeling results and experimental results of other researchers. FRP materials, particularly in the form of unidirectional strips, provide a highly effective method of structural intervention in masonry walls. However, the selection of the reinforcing pattern (positioning of the strips) still remains a problem. Usually in traditional technique have been used horizontal and diagonal FRP strips for strengthening of masonry walls. This study obtains the new pattern of FRP strips for strengthening masonry walls under monotonic loading with using of topology optimization and struts and tie model. This methodology ha bee implemented i a computer program that enable the definitio of the locations where FR stri should be placed i masonry wall subjected to in-plane loading. Results showed that the new pattern used in this study had more load capacity and ductility in comparison with traditional pattern such as horizontal and diagonal pattern. Key words Unreinforced masonry wall (URM), Reinforced masonry wall, FRP strips, Monotonic loading, Strut and tie model, Topology optimization, new pattern of FRP strips.