Abstract: Yunnanites coriacea was an endemic species of China. In order to understand the cytogenetic characteristics of different populations of Y.coriacea, the chromosome karyotype and C-band patterns of 2 geographic populations of Y.coriacea were studied by squashing and BSG chromosomal banding technique. The results showed that the 2 geographic populations had a diploid chromosome number of 2n (♂)=19 with a fundamental number (NF)=19, all chromosomes were telocentric and an XO sex-determining mechanism. The karyotype formula of Y.coriacea was 2n(♂)=3L + 6M + X, large and medium, and the X chromosome was the first element in size. The C-band karyotype analysis indicated that there were only 10 centromeric C-bands with a total of heterochromatic content (THC) was 10.67% in Kunming Western mountain population while the population in Dongchuan tuobuka had 10 centromeric C-bands and 8 terminal C-bands, and the total of heterochromatic content was 29.53%. Combining the external morphological differences of the 2 population, It could be considered as 2 different geographic subspecies.