Abstract: Short-term Culture in vitro was performed on the biopsy material obtained from a metastatic focus of malignant teratoma in lymph node,Karyotype analysis indicated that these cancer cells are near diploid and hyperdiploid with a model chromosome number of 45. In comparison with nomal diploidy,the number of chro-mosome E group in cancer cells is increased, while that of Ggroup is reduced. The chromosomal aberration of cancer cells involved gap,break, deletion, and fragments, In additioa. several marker chromosmes were observed.