The thesis presents a computer program for the design of a double-reinforced concrete section to axial- bending and shear strength in ultimate limit states. The program is developed in Visual C#® programming language by the author of this thesis. When defining the maximum axial-bending resistance of RC section the following factors are taken into consideration: the assumption of straight cross-sections and the compatibility of contact deformation of the reinforcement with the surrounding concrete. However, the tensile load of concrete in the account is ignored. Interdependency between stress and strain in concrete is considered according to the stress-strain diagram of concrete cylinder test, given by a parabola and a straight line. The interdependency between the stress and the reinforcement deformation is considered according to an idealized antisymmetric bilinear diagram for reinforcement steel. In the analysis of axial and bending resistance of the concrete cross-section the latter is divided into subsections and panels. The program allows the calculation of the minimum quantity and symmetrical quantity of longitudinal reinforcement. In determining the shear resistance of RC cross-section the following factors are considered: the shear bearing capacity of the non-cracked concrete section, the friction between the grains of the aggregate along the shear cracks, and the dowel effect of longitudinal tensile reinforcement in the shear crack. If the contributions mentioned are not sufficient to bear shear load, shear resistance sectional proof is performed based on the model of planar truss consisting of tensile zone, compressive tie in concrete, and shear reinforcement. Adequacy and applicability of the developed computer program is illustrated in three different computational cases.