Starch is the most important carbohydrate in the human and animal diets and it also has numerous industrial applications. Starch is widely used as a key material for processed foods such as bread, pancakes, cereals, noodles, pasta, porridge and tortilla. Increasing the starch content in food crops is one of the important targets for crop breeding. We used a starch-iodine test to identify varieties with high starch content in 2354 soybean germplasm collection and found a total of 126 germplasm that showed a strongly positive reaction. We quantified starch content from highly stained 7 soybean accessions by standard method (glucose-oxidase). As results, starch contents of 7 soybean germplasm were 2.81~4.55%, whereas the weakly stained controls showed low starch content with less than 1%. We also measured the contents of protein, fatty acid, water potential and free sugar in 7 soybean germplasm with high starch content. High starch germplasm showed lower protein content, while low starch germplasm showed higher protein content. Our results suggest that the increasing of starch content could affect protein level in soybean seed.