The authors investigated steel 03Kh18N11 with 0. 002-0. 018% sulfur and 0. 04-1. 35% manganese, the same steel with higher sulfur contents (0. 14 and 0. 18%), steel 12Kh18N10T (0. 0075% S, 0. 04%Mn, and 0. 4% Ti; 0. 018% S, 1. 35% Mn, and 0. 4% Ti), and steel 03Kh17N14M3 (0. 013% S, 1. 55% Mn, 2. 9% Mo). Experiments were performed at 20 degree C in 0. 1 N HCl and 0. 1 N H//2SO//4. The corrosion rates were calculated.