Cervical carcinoma is the 1st most common malignancy in korean females. HPV have been strongly linked to progression of cervical carcinoma. E6 and E7 as a small DNA virus encoding two major oncoproteins of HPV can act together to produce efficient immortalization of primary human epithelial cells, providing further evidence for the role of HPV in tumorogenesis. It is important to pursue the development of Immortalized human epithelial keratinocyte(IHEK) culture model which could be related to the pathogenesis between cervical and oral carcinoma. If we establish IHEK transfected by E6E7 gene, IHEK will be accepted as a model system for HPV-linked cervical carcinogenesis. The purpose of this study were to culture primarily normal human epithelial keratinocyte(NHEK), and to establish IHEK for applying these results to cervical and oral carcinogenesis in the future. The obtained results were as follows. 1. After 7-9 passages, cultured NHEK was almost senesce and disappeared, but cultured IHEK showed most basal cell and monolayer of polyhedral cells under 0.05mM Ca++, while small area of stratification and flattened epithelial cells with irregular border under 1.2mM Ca++. 2. The cultured IHEK showed relatively resistant growth to high calcium condition. 3. The mRNA E6E7 in cultured IHEK by RT-PCR was detected. 4. During the terminal defferentiation in cultured NHEK and IHEK, increase of insoluble cornified cell envelope formation was accompanied with induction of TGase 1 activity. But the cultured IHEK showed less CEM and TGase 1 activity than those of cultured NHEK. 5. Cultured IHEK showed non-tumorogenecity, but week anchorage independence. From the aboving results, we have developed technique to transform NHEK into IHEK by transfecting cells with E6E7 gene. Cultured IHEK was established as intermediate stage cell for studying the pathogenesis of human cervical carcinoma.