The aim of our study was to analyze the expression of one of the markers of progenitor cell of different cell types - CD 117 (C-kit) - in human pancreas during prenatal development. The pancreas of human embryos and fetuses at 4-28 weeks of gestation as well as of infants aged up to 2nd postnatal month, was studied. In histological sections, the immunocytochemical reactions were performed with the antibodies against C-kit, insulin and glucagon. In situ hybridization was used for detection of proinsulin mRNA. First cells expressing C-kit were found in human pancreas at 8.5 weeks of gestation among ductal epithelial cells. At 11.5 weeks of gestation these cells were found to segregate from the ductal epithelium and start to form islets. From 8.5 weeks of gestation C-kit positive cells started to express glucagon and proinsulin mRNA, and after 11.5 weeks they also expressed insulin. Islet C-kit positive cells coexpressing both glucagon and insulin, were also found after the birth. It may be concluded that C-kit positive endocrinocyte progenitor cells are common for pancreatic islet A- and B-cells and they are preserved in he islets after the birth.