One of the most important advantages of using Steel Plate Shear Walls in structures as a lateral load system is the possibility of creating openings with various shapes, sizes and locations in the steel plate. Since the existence of openings in steel plate shear walls, can reduce stiffness and ultimate strength of the panel, the various effects of creating openings should be studied. In this paper, the behavior of stiffened steel plate shear walls with two symmetric openings with variable aspect ratios of the central panel between the two openings is studied. This paper considers the central panel,in unstiffened case. Numerical modeling is done using ABAQUS. The openings are classified into three categories: 1) constant width and height, 2) constant width and variable height, and 3) variable width and constant height. It is found that stiffening of the central panel has no serious effect on the reduction of stiffness and ultimate strength of the panel. Also, results show that the only effective parameter on the stiffness and ultimate strength of the samples is the width of the openings, as the width of the openings increases, stiffness and strength decreases.