Abstract:The present paper reports chromosome numbers and karyotypes of five species and fourteen varieties of Rosa from China. The results are as follows: the small-flowered forms with 2n=2x=14, but a few are mixoploids; the mediumflowered ones with 2n=3x=21; the big-flowered ones with 2n=4x=28. The karyotypes of most cultivars are made of m and sm and a few with st chromosomes. They fall into three types: 1A, 2A and 1B.