Psoriasis is a chronic skin disease characterized by the activation of various T cell subsets secreting IFNγ, IL-17, and IL-22, dendritic cells producing TNFα and IFNα, and other immune cells including neutrophils and mast cells. Keratinocytes respond to different cytokine signals orchestrating innate and adaptive immune responses. In vitro studies sought to clarify the cytokine effects on keratinocytes in order to evaluate the centrality of these mediators in psoriasis pathogenesis. The aim of this review is to highlight the relevance of this peculiar in vitro approach in investigating cytokine effects on skin or multilayered epidermis. Particularly, we reported keynfindings supporting the cytokine role in psoriasis pathogenesis.