Human amniotic epithelial cells (HAECs) are formed from amnioblasts, separated from the epiblast at about the 8th day after fertilization. Recent studies suggest that HAECs can produce various biologically active substances. In this study, the effects of cultured HAECs on keratinocytes were investigated. First of all, the effect of the medium conditioned by cultured HAECs on the proliferation of keratinocytes was examined. The conditioned medium significantly enhanced the proliferation (P<0.05). Next, the effect of co-culture with HAECs was also examined. The keratinocytes formed a stratified epithelium on day 7 after the start of co-culture. The cultured epithelium formed by the co-culture was five to six layers thick, could be detached by dispase treatment, and had sufficient strength as a sheet. These results suggest that HAECs will be a novel supplemental material for the tissue engineering of skin.