Anti-TNF therapy has been found to be a new effective therapeutic option for many autoimmune diseases, such as: rheumatoid arthritis, ankylosing spondylitis, Crohn’s disease, psoriatic arthritis and psoriasis. TNF inhibitors reduce the signs and symptoms of an active inflammatory disease and improve the quality of life. Anti-TNF therapy has been approved by the European League Against Rheumatism for the treatment of spondyloarthropathies. Of late, attention has focused on some new data about their skin adverse effects, such as infection, vasculitis, eczema, interstitial granulomatous dermatitis and discoid lupus. Among the most paradoxical skin reactions are the psoriasiform eruptions that have been described during anti-TNF treatment in patients with many autoimmune diseases, excluding psoriasis and psoriatic arthritis. We report a case of psoriasis in a 53-year-old patient with ankylosing spondylitis during etanercept therapy.