Abstract:According to the difference of fruits, the genus Gynostemma Bl. was divided into two subgenera: Suben. Gynostemma and Subgen. Triostellum. This paper reports chromosome num-bers of 8 species and 1 variety including 20 populations of this genus. Among them, 4 species and 1 variety are the first reported. Chromosome numbers are usually 2n=22, 33, 44, 66, and 88, the two subgenera have the same basic chromosome number: x= 11. Polyploids are frequent in several species, and triploid and diploid individuals of G. pentaphyllum var. dasycarpum were observed in the same population. The polyploidy is usually related to the morphological feature, reproduction and geographic distribution. Some species with diploid are distributed in small regions, such as G. microspermum, G. laxifiorum, G. guangxiense and G. pentagynum, and polyploids are usually ob-served in some species, such as G. cardiospermum, G. longipes, G. yixingerse and G. pentaphyllum, distributed in larger regions.