Flooding is one of the most frequent climate disasters in eastern and southern Asia.Development of cultivars tolerant to submergence is an effective way to avoid the threat of flooding to soybean production.The objectives of the present study were to evaluate the submergence tolerance of young seedlings of released cultivar populations from different Asian regions,to reveal their genetic variation,and to identify elite germplasm with submergence tolerance for breeding purpose.The 350 released cultivars from Huang Huai valleys and Southern China,as well as other 15 Asian countries were sampled and tested in pot experiment at young seedling stage under artificial flooding condition.The relative death rate was used as major indicator with relative yellowing rate and relative withering rate as reference indicators.The results showed that the indicator system was effective in evaluating the submergence tolerance at young seedling stage of soybean.There existed great genetic variation of submergence tolerance in the Asian soybean cultivar population with relative death rate varying from 4.8% to 212.0%.In each eco-region,i.e.Huang-Huai valleys,Southern China,East Asia,Southeast Asia and South Asia,the relative death rate of the cultivars distributed as a similar single peak curve with genetic coefficient of variation more than 21 24%,especially in Huang-Huai valleys with its range covering the whole population.There exist elite tolerant materials in each eco-region,especially in Shandong and Jiangsu Provinces,and seven,four,one,one and two in a total of 15 most tolerant materials were selected from the respective eco-regions.Among them,some selected tolerant cultivars have their tolerance inherited from the tolerant parents,Juxuan 23,Nannong 493-1,Qiandou No.2,after tracing their pedigree;the four selected exotic tolerant cultivars are characterized with resistance to some diseases,therefore,could be used as elite parents for broadening genetic bases in breeding for submergence tolerance in China.