Leaf weight,stak weigh,leafand stakweight ratio and heigth of Astragalus Adsurgensall are morphologically important characteres of its above-ground part.It has been studied that therelationship bewteen those characteres and its forage yeild,as well as impacting of soil moisture andfertilizing amount on those characteres with the plot experiement.The resultes show as following:The grass yeild increases with leaf weight as the power function:The grass yeild is directly proportion to its stalk weight. The ratio of grass leaf and stalk weight decreases with its grass mass as negtive power func-tion.The changes of its heigth with time can be very good fitted to the Logistic equation. The effectof soil moisture and fertilizing amount on heigth,stalk weight and leaf weight are all excielentlypositive, which moisture effect is greater than that of fertilizing amount.