Genetic mutations of alfalfa floral properties,including calyx diameter, coronary length, flower number per raceme, raceme number per twig, flower number per unit area, percentage of flicked flowers, excreted nectar volume, sugar concentration in nectar and contents of sucrose, fructose and glucose in nectar,have been studied with both morphological markers and RAPD markers. The results showed that the genetic variation of floral properties is from 0.80% to 92.30%, of which the content of glucose was the most significant one with the variation from 0.01 to 0.53 mumol/L (p0.05), and the sugar concentration was the most insignificant one (P>0.05). RAPD analysis showed that variances of genetic distances was from 0.21 to 0.35, among which the most significant one was WL323 and Shanbei, and the most insignificant one was Derby and Prime. Thus it can be seen that genetic diversity of floral properties among these varieties of alfalfas is abundant.