A human diploid fibroblast cell line derived from normal abdominal skin of a 17-year-old female patient with ovary carcinoma was established and designated as HSF 79-2. The cultivation of skin fragments was employed in the primary explantation. The medium used was McCoy 5A supplemented with 15～25% calf serum. The grown fibroblasts were succesively subcultured at 1 to 2 split and stopped at the 45th to 54th passage.Having reached confluence the cells still had the ability to divide during 16 months observation if the medium was changed periodically. They displayed the property of dense growth and forming heavy, multilayer sheets, which became a visible membrane to the naked eyes. Under histological examination the membrane had the appearance of connective tissue. Part of the cells were subcultured again after 3,6, and 12 months maintenance in the same culture flask. Their growth character, ploidy, and the generation time were similar to that of the cells passaged normally.The characteristics of this cell line mentioned above appear to be shared by other diploid fibroblasts. It might be used for preserving cell lines and as a model for studying cell motility and differentiation.