Objective To study the cytogenetic changes in HPV-immortalized cells(SHEE)for further investigating the esophageal carcinogenesis. Methods Giemsa staining was used to show the modal number of chromosomes.G-banding was done to observe the chromosomal aberrations.Fluorescence in situ hybridization(FISH)of the interphase nuclei with the centromere probes of chromosome 1,7 and 8 were performed to determine the numerical abnormalities. Results The modal numbers at passage 10 and 20 were 58-63 and 57-64, respectively.Passage 61 had a bimodal distribution 58-61 and 63-65.The structural aberrations could almost be found in all of karyotypes.The following structural aberrations were identified:1.del(1)(q12);2.del(1)(p32);3.der(4),t(4;?)(q31;?);4.der(5),t(5:?)(q31;?).FISH results showed that trisomy 1 and tetrasomy 7 markedly increased with the increase of passages and disomy 8 kept in faint change in all passages.Conclusion The modal number moved right slowly in the graph of the modal distribution and the increases of chromosomal numbers were in imbalance with increases of passages of SHEE.The structural aberrations of chromosome were found in most of karyotypes.Our results suggest that the cell immortalization is a multistep process involved in the multiple chromosomes.;