Abstarct: In this thesis an attempt has been tried to consider the effective parameters on the stress distribution around a regular polygon hole in symmetric laminated composite plates by particle swarm optimization (PSO) to introduce the optimum parameters to achieve the lowest value of stress around the hole. Design variables include the geometry of cutout, bluntness, rotation angle of cutout, fiber angle, load angle and material properties in symmetric laminated plates. The finite element method has been used to verify the accuracy of analytical results. Comparison of two methods demonstrates the accuracy of present analytical solution. In this study, an analytical method is used to calculate the stress components around of various shape hole. According to this method using conformal mapping, the development of Lekhnitskii method that was just for the circular and elliptical hole was used the other holes. The results presented in this study show that by selecting appropriate shape of hole and optimal parameters related to perforated symmetric laminated plates, stress concentration factor can be significantly reduced and even achieved to less stress concentration factor from stress concentration caused by a circular cutout.