The experimental results on development character of flowers, pods and seeds in 24 vegetable soybean cultivars showed that there was difference between different maturing types cultivars in reproductive organ development. Compared to late cultivars，Early cultivars were more fastin flower and pod development, short in time and fast in pod shedding. The seed formation focused in three period: fresh seed weight was formed in middle and later stage, pod rind weight in middle and beginning stage, pod weight in middle stage. The developmentin middle stage was basis of seed formation and key ofyield accumulation. The result suggested that 20 days was is the suitable flowering and podding period for vegetable soybean cultivar selection.