Fresh soybean stored at 4 C in air or nitrogen atmosphere showed gradual decrease in soluble sugars during 28 days of storage. Soybean stored in open air at 25 C showed significant accumulation of oligosaccharides; whereas soybean stored in nitrogen atmosphere at 25 C showed significant degradation of all sugars. Low temperature was more important than atmospheric condition in preserving the nutritional and sensory values of fresh vegetable soybean. Soluble sugars decreased in soybean seeds during water blanching treatment as a result of leaching. The presence of pod effectively impeded the leaching of sugars in water blanching treatment. Steam blanching preserved soluble sugars in both vegetable soybean pods and seeds than water blanching. There was no significant change in sugar composition of blanched vegetable soybeans during 6 months of frozen storage. This research information will be useful in selecting post-harvest processing and/or storage method for vegetable soybean.