An analysis of the relationship between plasma cytokines and the effectiveness of treatment with TNFαinhibitors was performed in 81 patients with moderate-to-severe psoriasis. Treatment efficacy was assessed by PASI score, and patients were classified into a positive effect (PASI≥75) and no effect group (PASI≤50). A positive effect was reached in 11 (41%) patients for etanercept, 14 (52%) for adalimumab, and 26 (96%) for infliximab. Data analysis did not show differences in baseline TNFα levels and subsequent treatment effectiveness. The CART algorithm showed that at the baseline level of VEGF ≥ 32 pg/ml and IL17F < 26 pg/ml, there was an 83% probability of a positive effect. Random forest analysis showed the importance of VEGF, ICAM1, sCD40L, IL17F and IL31 baseline levels in the prediction of treatment effectiveness. Significant differences between the groups before/after the treatment were found only for TNFα: the median values were more than 50 times higher in no effect compared with positive effect group. There were differences before/after therapy in the levels of IL20, ICAM1, IL22, IL23 in the no effect group. The treatment affected the cytokine profile in most cases regardless of the effectiveness of therapy.