We took cultures of many human renal cell cancers and established two cell lines in vitro which were derived from the spindle cell carcinoma of a 67-year-old woman (MR-1) and from the dark cell carcinoma of a 74-year-old woman (MR-2). Using a nude mouse, we established the cell line in vivo (MRV) which was derived from the same patient as that for MR-1. MR-2 was maintained through 140 passages and MR-2 110 passages. MRV was maintained through 7 passages. With passaging, the characteristics, the doubling times and the chromosomal numbers of these cell lines changed, these changes were caused by the transformation, the mutation and the selection of the passaging cells. The study of the sensitivity test of the anti-cancer drugs to the established cell lines was done using the radioisotope uptake assay in vitro and the tumor volume changes in nude mice in vivo. We considered there were differences between the effective drugs used in vitro assay and in vivo assay. As to radioisotope uptake assay, it is difficult to judge the exact effect of the plant alkaloids, which inhibit the cell division and are dependent on the contact time, and we may overestimate the effect of the cytotoxic antibiotics. Further investigation on the methodology of the sensitivity test of the anti-cancer drugs would be necessary for the clinical application.