Objective To investigate the effect of anti-Helicobacter pylori (Hp) treatment on Hp-positive patients with psoriasis vulgaris and the possible mechanism of Hp infection and psoriasis vulgaris. Methods A total of 50 patients with Hp-positive psoriasis vulgaris diagnosed in Department of Dermatology, Affiliated Hospital of Chongqing Three Gorges Medical College from December 2019 to September 2021 were selected and randomly divided into experimental group and control group, with 25 cases in each group. The experimental group was treated with halometasone cream and calcipotriol ointment combined with quadruple anti-Hp therapy, and the control group was treated with halometasone cream and calcipotriol ointment. The PASI scores and serum IL-17 levels of the two groups before and 1 month after treatment were compared. Results The PASI score of the two groups after treatment was lower than that before treatment, and the experimental group was lower than the control group, the difference was statistically significant (P<0.05). The level of IL-17 in the two groups after treatment was lower than that before treatment, and the experimental group was lower than the control group, the difference was statistically significant (P<0.05). Conclusion AntiHp treatment for patients with Hp-positive psoriasis vulgaris is conducive to improving the clinical efficacy of patients, and Hp infection may be involved in the occurrence and development of psoriasis by inducing elevated serum IL-17 levels.