An algorithm for computer simulation of corrosion degradation of the rod elements surface under conditions of simultaneous influence of aggressive medium and complex bending was constructed. Mathematical models of corrosion taking into account the relationship between the stress-strain state parameters and the corrosion damage rate was used. To calculate the cross section geometrical characteristics and stress values that are change in time as a result of corrosion, the rod cross section contour is discretized by its uniform splitting of a finite set of points and the subsequent approximation of the contour by linear splines. The problem of calculating of structural element durability is solved by integrating of the mathematical model equation of corrosion damage. In this case, the change of the position of the each surface point of the material (cross-section) in the process of corrosion degradation is determined. At each integration step it is assumed that each individual point of the contour get dislocation in the depth of the material in direction perpendicular to the cross section contour and the corrosion magnitude at a single point of the surface does not depend on the corrosion magnitude at adjacent points. The means of algorithm realization constructed in the work allow to model corrosive deterioration of a rod of arbitrary cross-section to its complete degradation. Numerical results, obtained using of the developed algorithm, allows to make a comparative analysis of changes in time of maximum stresses, perimeter and area (material loss rate) of a rod element of various cross section shapes (rectangular, round, square box, channel, and two-tailed) for the case of their equal initial area and with equal values of maximum stresses at the initial time moment. It is shown that the greatest loss of material (cross section area) as a result of corrosion damage is inherent to cross sections with a larger perimeter.