This article assesses the resistance of brown forest soils of the Republic of Crimea, the Western and Central Caucasus to pollution by lead, chromium, nickel, and copper, and develops regional maximum permissible concentrations of these heavy metals. Soil contamination was modeled under laboratory conditions. Heavy metals were added in the form of oxides. Soil stability assessment was carried out by biological indicators. The brown forest soil of the Republic of Crimea proved to be the most resistant to pollution. The higher stability of the brown forest soils of the Western Caucasus relative to similar soils of the Central Caucasus, apparently, is determined by the higher content of organic matter in them, despite their lower acidity. Heavy metals formed the following series in terms of ecotoxicity for brown forest soils: Cr> Cu ≥ Ni ≥ Pb. The values of regional maximum permissible concentrations of lead, chromium, nickel and copper in the brown forest soils of the Crimea, Central and Western Caucasus are proposed.