Primary and subcultured epithelial cells obtained from the human ectocervix and endocervix were compared by light, immunofluorescent, and electron microscopic techniques. In culture, both cell types were consistently free of surface-associated fibronectin as revealed by immunofluorescent studies. Ectocervical cell colonies exhibited a stratified appearance, where as endocervical epithelial cells grew in a single layer with smooth overlapping of adjacent cells. In addition, the surfaces as well as the cytoplasmic organellar structures of both cell types showed many characteristic features related to the epithelium of their origin. These features were retained with the aging of the cells and were seen also in subcultures. These cultures should permit observation of the effects of steroids, as well as viral and chemical carcinogens, on the ultrastructural integrity of the epithelial cells.