Application of different kinds of mineral waters and peloids on the skin exerts mechanical, thermal and chemical effects. Significant reduction of inflammation and increased differentiation of keratinocytes may explain why balneotherapy has positive clinical effects in psoriatic patients. In vitro models have shown that thermal water stimulates interleukin-2 production after cell stimulation by staphylococcal enterotoxin B, and reduces interleukin-4 secretion. After balneotherapy, a significant decrease in Psoriasis Area Severity Index (PASI), associated with a significant reduction of interleukin-8, Staphylococcus aureus colonization and enterotoxin N, have been reported in patients with psoriasis. Mineral water was found to have inhibitory in vitro effects on substance P, TNF-α release and antigen-induced cell degranulation. Immunomodulatory effects of water depend on its content. Sulfur waters have beneficial anti-inflammatory, keratolytic, and antipruriginous effects and also possess antibacterial and antifungal properties. The effectiveness of balneotherapy in the treatment of psoriasis has been reported in many studies conducted all over the world. The majority of studies were conducted at the Dead Sea coast. Investigations showed that balneotherapy factors are important therapeutic factors in the treatment of psoriatic patients. The first and only comparable study of this kind in Serbia, was conducted in Prolom Spa with satisfactory therapeutic results.