Modern supporting reinforced concrete structures, i.e. columns, piers, frame legs, etc., are characteristics by their higher slenderness. Effects of external forces are on these structures are significantly dependent on their deformations. In the reliability assessment of these structures it is necessary to deal with the equilibrium of internal and external forces acting on deformed structure. Rapidly growing potential of computer technology allows utilize fully probabilistic methods of reliability assessment of tructures. The subject of this paper is probabilistic safety assessment of slender reinforced concrete column loaded by eccentric compressive force. The solution is based on fully probabilistic SBRA method using Monte Carlo simulation technique.