In the present graduation thesis I deal with the conduct of timber columns under influence of combined axial and bending actions with emphasis on problems of buckling. These problems are specific with timber for which significant non-linear behaviour under compression stresses is characteristic. To this purpose I have elaborated a computer program for numerical simulation of nonlinear elastic response the elaboration of which is in greater detail presented after review of theoretical background. Presented are also the demands and proceedings according to European standard for design of timber structures Eurocode 5. I compare the results which follow these demands with results of my computer program.