Psoriasis is a chronic skin disease characterized by benign proliferation of epidermal cells. The most important seems to be: excessive divisions of keratinocytes in the basal-cell layer, its abnormal maturation and increase of angiogenesis. Epidermal growth factor (EGF) is regarded as a factor playing probably the major role in pathogenesis of psoriasis. It regulates cell growth, and stimulates proliferation and differentiation through binding with the EGF receptor (EGFR). In active psoriatic lesions regular increase of EGFR expression in all layers of the epidermis is observed. Blockage of EGFR with monoclonal antibodies inhibits proliferation of keratinocytes. In this review article we present data on the importance of EGF in pathogenesis of human skin diseases, indicating the need for further studies on its role in the pathogenesis of psoriasis.