Objectives: Risankizumab (RIS) is an innovative drug registered by EMA in 2019 for the treatment of moderate-to-severe psoriasis. It has demonstrated high efficacy, best characterized by a response rate of PASI90 achieved by 75% of patients in a clinical trials. The aim of this study was to evaluate the cost-effectiveness of RIS compared with ustekinumab (UST) for the treatment of severe psoriasis from the perspective of a Polish public payer. Methods: An excel-based Markov model was developed to simulate a cohort of patients over 5-year horizon. Transition matrices were fitted to the aggregate-level data from UltIMMA-1 and UltIMMA-2 trials. Relapse rate was assumed to be the same for both treatments. The treatment regimens of both treatments were assumed to be intermittent. In line with current Polish clinical practice, time limit for a single cycle of treatment with UST was set at 48 weeks and with RIS at 96 weeks. The outcome was incremental cost-effectiveness ratio (ICER), calculated in two ways: as a ratio of incremental cost to incremental quality-adjusted life years (EUR/QALY) or a ratio of incremental cost to incremental symptom-free life years (EUR/PASI100 LY). Results: The model indicates that patients treated with RIS will gain an additional 0.91 life years with a response of PASI 100 compared to UST. The incremental health benefit expressed in QALYs was 0.14. ICER was 211.8K EUR/QALY and 33.3K EUR/PASI100 LY. Conclusions: ICER expressed in QALYs is above the current cost-effectiveness threshold in Poland, however it falls in a range of ICERs that is typical for this class of drugs reimbursed in the treatment of psoriasis. Other anti-interleukin agents (ixekizumab, ustekinumab, secukinumab) given their list prices have demonstrated ICERs from 50K to 280K EUR which were all beyond the acceptability threshold for reimbursement in Poland.