Abstract: Psoriasis is an autoimmune disease associated with T lymphocytes.Recent research has shown that besides T helper type 1 cells,regulatory T (Treg) cells,especially the Treg and T helper 17 (Th17) cells whose generation is induced by the forkhead-box/winged-helix transcription factor Foxp3,play an essential role in the pathogenesis of psoriasis.Among them,Foxp3 + Treg cells play a key role in the exacerbation of psoriasis when the balance between immunosuppression and immune activation is shifted.The cytokines produced by Th17 cells,including interleukin (IL)-17A,IL-17F,IL-22,IL-23,IL-36,tumor necrosis factor (TNF)-α,and so on,play important roles in the initiation and progression of dermatoses.Psoriasis is a muhifactorial disease with the collaborative involvement of many immune cells including Treg and Th17 cells,as well as cytokines.