Abstract:Chromosome numbers and of the two Cyccls species from China are all 2n=2x=22, and the karyotypes are classified to be 3B according to stebbin＇s category. The karyotype formulas are 2n=2x=22=4m＋2sm＋4st＋12T for C. hainanensis, and 2n=2x=22=2m＋4sm＋4st＋12T for C. szechuanensis subsp.fairylakea. The two karyotypes are reported for the first time. The results support that Cycas can be divided into two groups based on the chromosome data.