The purpose of this study is to compare the effectiveness of artificial balneotherapy (AB), phototherapy (PT) and artificial balneophototherapy (BPT) in the treatment of plaque psoriasis, evaluating the plaque area, alteration of skin pigmentation, Psoriasis Area and Severity Index (PASI) score determination and quality-of-life assessment by Short Form 36 Health Survey (SF-36) and Psoriasis Disability Index (PDI) scores during the month of treatment. Methods: Experimental study, prospective, randomized, single-blind. 14 subjects participated from the city of Talca, Chile medically diagnosed with psoriasis, more than one plaque in the skin without topical treatment voluntarily. All subjects completed the study that consisted of 12 sessions.