Abstract:The chromosome numbers and morphology in four cultivars of Siraitia grosvenorii (Swingle) C. Jeffrey ex Lu et Z. Y. Zhang were observed with root tips and tissue culture materials. The results show that the chromosome number is 2n= 28. The chromosomes are relatively small, less than 1.4 μm, and the morphology of which in different cultivars are distinctive from each other. The ratios of the longest chromosome to the shortest among the four cultivars range from 2.00 to 2.46. The subordination of Siraitia grosvenorii to the genus is discussed.