The study presents results of pitting corrosion tests and analysis of chemical composition of X2CrNiMo 17-12-2 steel surface layer with diversified strain hardening and the method of surface preparation after 30-day exposure to artificial urine. Samples with electrochemically polished as well as with electrochemically polished and chemically passivated surface were selected for the tests. Electrochemical passivation was applied in order to obtain extremely smooth surface (Ra0.16 m). Pitting corrosion tests were performed by means of potentiodynamic method, where analysis of chemical composition of the layer formed on the steel surface was conducted using X-ray photoelectron spectroscopy (XPS). The tests were carried out in order to determine suitability of X2CrNiMo 17-12-2 steel with modified surface and diversified strain hardening for production of wire used in urology.