We have analyzed the data on stress corrosion cracking of steels of various grades in acidic H2S–CO2–Cl– solutions. For the active region of corrosion, we have obtained the dependence of the lifetime and the steady-state corrosion rate on external (concentration of solution components, temperature, and tensile stress) and internal parameters of corrosion (Cr, Ni, and Mo doping level and conditional yield stress for steel). The resultant dependences will make it possible to estimate the corrosion behavior and the possibility of using steel in an aggressive environment without resorting to durable and costly natural tests.