Animal-based food products play a significant role in the current U.S. diet. In 2003, the total meat consumption per capita was 90.5 kg/year [U.S. Department of Agriculture (USDA) 2005]. Since the U.S. has a high consumption of animal-based food products, the animal feed ingredients are fundamentally important. The ingredients can affect not only the quality of the animal-based food products, but also the potential human health. The U.S. is the largest producer of animal feed in the world (Gill 2004). Feed ingredients might include grains, milling byproducts, added vitamins, minerals, fats/oils, and other nutritional and energy sources. And kinds of feed ingredients are produced to use, like DDGS and soybean meal. Recently, some co-products of energy production, like DDGS are used as feed ingredient worldwide. This kind of co-product is nutrient rich and meets the requirement of animal feed nutrition. Since these food ingredients are used worldwide, they must be transported a long distance to some domestic and international market. And sometimes they are stored for a long time before be used. So during transportation and storage, ingredients often became restricted. This is a major problem that can affect the quality of ingredients. These issue most likely results from many factors, including ingredients’ moisture content, particle size, temperature and relative humidity of air or pressure. The objective of this study was to investigate potential factors affecting flowability of feeding ingredients, as well as examines the effect of three moisture content levels (10, 20 and 30% db) on the resulting physical and flow properties of feeding ingredients. Certain amounts of water were added to adjust moisture content of ingredients and Carr indices were used to quantify the flowability of each ingredient. The results showed that moisture content had significant effects on physical and flow properties. According to Carr indices, flowability generally declined with increased moisture content. Using these, the best condition can be found for transportation and storage to maintain the good quality for ingredients when they are used.