Abstract: Cytogenetic research on calli and regenerated plants of hybrid between Triticum aestivum L. cv. Fuhuho and Leymus paboanus(Claus) Pilger (2n=84) indicated that striking variation in karyotype occurred in the callus cells. Most of the callus cells were aneuploid and the dominant changes of chromosome structure were telocentric chromosomes, dicentric chromosomes and cyclic chromosomes. Such changes made chromosome and gene recombination possible because of their unstabilities and also increased resistance to leaf disease in the regenerated plants. The authors further discussed the causes of these variations and the application of in vitro technique in transfer of benificial genes from polyploid alien species to wheat.