Stored soybeans are subject to deterioration. Free Fatty Acid development in soybean oil is always known to accompany the deterioration. Storage fungi is the major factor causing soybean deterioration that can bring substantial losses to processors. Different varieties may have different resistance to the development of all or some fungi. Samples of popular soybean varieties were hand harvested and stored at 22% moisture content and temperature 26 C. No differences were found in C02 evolution. Significant differences were found in FFA development among three varieties.