The research described in this paper is devoted to short term anodic nitriding of grade 45 steel with postquenching (nitroquenching) in the aqueous solution of ammonia and ammonia chloride. The mod ified layer structure, as revealed, is composed of alternate layers: a surface oxide layer composed of FeO and Fe 3 O 4 ; a layer of dispersed nitrides Fe 4 N and Fe 2-3 N with retained austenite; next, a martensitic zone com posed of nitrogen and carbon; and the initial nitrogen enriched ferrite-pearlitic structure. It is found that concentrations of electrolyte components and processing conditions affect the formation character and prop erties of diffusion layers. The possibility is shown for obtaining a nitroquenched layer 130 μm in thickness with a surface microhardness of to 1200 HV with a decrease in roughness R a from 0.57 to 0.55 μm, R z from 1.75 to 1.62 μm, and R max from 5.74 to 4.00 μm.