A series of nitrogen fixation characteristics, such as nodule nitrogen fixation activity, nodule ureide content and young stem ureide content were studied in the same latitude and differently evolutionary types of soybean.The results indicated that the nodule nitrogen fixation activity, nodule and young stem ureide contents were the highest in cultivated soybean and the lowest in wild soybean.The nodule nitrogen fixation activity, nodule and young stem ureide contents of semi-cultivated soybean were higher than those of semiwild soybean.