The results of this study showed that serum IL‐6 associated with neutrophils; IL‐18, CXCL1; IFN‐γ, TNF‐α associated with Th1; VEGF‐A associated with angiogenesis; and IL‐ associated with Th17 proliferation in patients with moderate to severe psoriasis (PASI score mean 21.6 ± 11.0,BSA score mean 32.67 ± 21.58) 17A were all significantly higher than those in normal subjects. The gene discussed is IL18; the disease is psoriasis.