Abstract: As an important ornamental plant Rosa multiflora is used widely in the greening of the city in our country. But there was no integrate research about the Rosa cultivars. Random amplified polymorphic DNA(RAPD) was used to analyze the genetic polymorphism of 2 Rosa species, 1 var. species and 20 Rosa multiflora cultivars. Sixteen primers amplified 175 DNA fragments, 151 (86.3%) of which were polymorphic. Different color cultivars had different genetic polymorphism with the white 75.16%, pink 73.46%, yellow 37.50%. Cultivars were taken for cluster analysis by the way of UPGMA. When LD was 0.667 material in experiment could be classified into three categories. The two parts were white-pink cultivars such as Rosa multiflora and modern cultivars of Rosa of which flower were larger. Yellow flowers were in anther part which was far away from other two parts. The cluster result revealed the evolution tendency of Rosa plants. Original character was white and simple petal. Modern character of Rosa cultivars was Larger and double flower. The Rosa of pink semi-double petal was the transition from wild species to modern cultivars.