A simply supported square perforated plate with bending moments is investigated using the boundary element method. Optimal location of the circular hole is sought by design sensitivity analysis and gradient projection method using the minimization of the elastic strain energy. Comparing the results of the boundary element method and the finite element method, the difference of the two results is within 8.9 percent. Sensitivity of the hole center is correct over 94.2 percent when compared with average slope from the sensitivity check. Consequently, it is confirmed that the best mechanical characteristics are achieved by minimizing of the elastic strain energy.
