OBJECTIVES: To assess the impact of psoriasis vulgaris treatment with tacalcitol on quality of life. METHODS: An epidemiological, observational, prospective and multicenter study of a cohort of patients with mild to moderate Psoriasis vulgaris has been performed. Patients have been treated with tacalcitol ointment (4 mg/g). Anthropometric and demographic characteristics of patients were recorded in addition to percentage of affected area and previous and current treatments. Symptomatology (erythema, desquamation and thickness) was evaluated by a scale from 0 (absent) to 4 ( maximum intensity of symptom). At follow-up (15 and 60 days) symptomatology and appearance of adverse effects were registered. Psoriasis Area Severity Index (PASI) was calculated at each time. Health related quality of life forms SF-12 and Psoriasis Disability Index (PDI) were completed at the inclusion and final visits. RESULTS: Seven hundred thirty one patients out of 1286 were included to perform quality of life analysis. (54.67% men and 45.33% women). Mean age was 43.59±15.48 years and BMI 25.07±3.84. Mean affected area at inclusion was 15.97%±8.14. Basal PDI was 29.20±14.30. Bigger values for PDI, and therefore worse quality of life, were registered in patients with PASI values between 10-50 (28.06±15.26) vs. those whose PASI values were below 10 (34.18±13.60 p <0.001). After 2 months of treatment, most of patients improved their quality life index: 85.20% for PDI, 51.78% for SF-12 physical domains and 83.30% for SF-12 psychical domains. CONCLUSIONS: Tacalcitol treatment has a positive effect on health related well-being, improving quality of life measured by unspecific scales and also by dermatologic indexes such as PDI. Tacalcitol treatment increases SF-12 scores, especially those for psychical domains, resulting in improvement on patients self-esteem.