Objective To explore the clinical efficacy of Jianpi Jiedu decoction combined with acitretin in the treatment of erythrodermic psoriasis. Methods A total of 56 patients with erythrodermic psoriasis who were treated in Changji Branch of the First Affiliated Hospital of Xinjiang Medical University from July 2018 to July 2022 were selected and divided into observation group and control group according to the random number table method, with 28 patients in each group. The control group was treated with acitretin, and the observation group was treated with Jianpi Jiedu Decoction on the basis of the control group. The clinical efficacy, proinflammatory cytokines [tumor necrosis factor (TNF-ɑ), interleukin 6 (IL-6), interleukin 8 (IL-8)] levels, psoriasis area severity (PASI score), skin disease quality of life index (DLQI) score, TCM syndrome score and adverse reactions were compared between the two groups. Results The total effective rate of the observation group was 96.42%, which was higher than 82.14% of the control group (P <0.05). The levels of TNF-ɑ, IL-6 and IL-8 in the observation group were lower than those in the control group (P <0.05). After treatment, the PASI and DLQI scores of the observation group were lower than those of the control group (P <0.05). After treatment, the scores of TCM syndromes in the observation group were lower than those in the control group (P <0.05). There was no significant difference in the incidence of adverse reactions between the two groups (P >0.05). Conclusion Jianpi Jiedu decoction combined with acitretin in the treatment of erythrodermic psoriasis has a good curative effect, which can reduce the level of pro-inflammatory cytokines, improve the clinical symptoms of patients, and has certain safety.