Expanding the scope of construction projects on the development of new technical solutions and on the reconstruction of existing ones is one of the goals of technical development. Mechanical constructing includes a series of activities from determining the requirements for the machine system through constructing and calculation to complete constructing development, to the extent that the technological development and the production itself can be carried out. Among other things, the stress states are checked in the calculations. For this reason, in this paper, special attention is paid to determining the distribution of the main normal stresses. The tests were performed on a rectangular plate with an elliptical opening in it. The tested plate was exposed to an axial static load, and steel was used for the material of the plate. The finite element method (FEM) and the ANSYS computer program were used to obtain the results on the distribution of the main normal stresses, and in order to verify the obtained results, a comparison was made with the theoretical results.