Abstract: Objective To investigate the levels of regulatory T cells in peripheral blood of patients with different types of psoriasis. Methods Flow cytometric analysis with monoclonal antibody was used to detect the percentage of CD4+CD25bright T cells in CD4+ T cells in the peripheral blood of 20 patients with psoriasis vulgaris, 15 patiens with psoriasis pustulosa and 10 patients with erythrodermic psoriasis, as well as the proportion of CD4+CD25hi-intCD127low/- regulatory T cells in CD4+ T cells in the peripheral blood of 10 patients with psoriasis vulgaris. Results The percentage of CD4+CD25bright regulatory T cells was （5.37 ± 1.99）% in patients with erythrodermic psoriasis, significantly higher than that in the healthy controls （P < 0.01）, patients with psoriasis vulgaris （P < 0.05), and patients with psoriasis pustulosa （P < 0.05）. There was no significant difference in the percentage of CD4+CD25hi-intCD127low/- regulatory T cells between patients with psoriasis vulgaris and healthy controls （（4.39 ± 0.84）% vs. （3.83 ± 1.68）%, P > 0.05）. Conclusion CD4+CD25bright regulatory T cells may be related to the pathogenesis of erythrodermic psoriasis.