Abstract: Section Camellia, belonged to the genus Camellia, is distributed in Japan, eastern and soutern parts of China. The results represented here showed that almost all the species of Section Camellia in eastern and southern China are diploids, and most of them in the Jinshajiang valley are tetraploids, while those in most parts of Yunnan Province are hexaploids. By using BSG C-banding method, the Cubands among populations studied here were different from each other,which was in accordance with their morphological variation of these populations. For each popu- lation, the Cusbands showed in the distal region of the chromosomes, and only two of them were detected to be homologous in all chromosomes showing C-bands of tetraploids and hexaploids, however, the number of chromosomes showing C-bandings decrease as the ploidy increase. Com-pared the results represented here with the data previously reported by other authors, it was found that the ploidy of the species in section Camellia gradually increased from southern China andeastern China, via Guizhou,to Sichuan and Yunnan Province.

Key words: Jinshajiang valley