Karyotypes of Dremomys pernyi from Kanding, Sichuan Province, China and D. pyrrhomerus from Nanling, Guangdong Province, China were examined. The karyotype of D. pernyi was of 2n = 40 and FNa = 72, while that of D. pyrrhomerus was of 2n = 38 and FNa = 70. Karyotype of D. pernyi from Kanding was different in 2n and FNa from reported karyotype of conspecific population from Taiwan, and it is suggested that the Taiwan population represents a distinct species D. owstoni from D. pernyi. The difference between karyotypes of D. pernyi and D. pyrrhomerus may involve at least a Robertsonian rearrangement and a heterochromatin addition.