A study has been made of the influence of microstructural parameters of dual phase ferritic-martensitic steels on their ductility with different stress state patterns and types of loading (uniaxial elongation and torsion). 05G2S2 steel was investigated after different types of preliminary heat treatment. The influence of microstructural parameters on resistance to alternating deformation was also assessed. Highest ductility is possessed by dual phase ferritic-martensitic steel produced with accelerated cooling from the intercritical temperature range after preliminary quenching from the monophase gamma-region.