The available CAE solutions are a significant assistance when carrying out engineering works. They facilitate conceptual design, design and carrying out strength calculations. These tools are very popular because of the simplicity of use and the ability to obtain quite accurate distributions of structural stress and strain. Unfortunately, when designing shafts the rotation angle values on supports are equally important. The present article draws attention to the essential problem of the misalignment of roller bearing assemblies caused, among others, by exceeded allowable angles of rotation. The article furthermore presents the results of the analysis which aimed to determine the influence of selected geometrical characteristics of the shaft as well as the bearing span on the value of the shaft angle of rotation at the supports.