Depending on the increasing world population, the need for energy is also increasing. However, fossil fuels cannot meet the increasing demand and cause the search for alternatives. Biodiesel can be a solution to this demand as an alternative fuel that can be used as a fuel source. Energy needs and the search for alternative energy sources have gained importance in the field of animal nutrition in recent years. Crude glycerine, which is the main by-product of biodiesel production, can be a solution to this search in the feed industry. Crude glycerine can be obtained at relatively lower costs for the feed industry. It can be used less than grain feeds such as corn, which is high in poultry mixed feeds. It has been stated that the gross energy of pure glycerin is approximately 4100 kcal/kg, the gross energy of crude glycerin is approximately 3600 kcal/kg, and the AMEn of crude glycerine is 3434 kcal/kg. This review article discusses the use of crude glycerine as an alternative energy source in broiler mixed feeds and its effects on different parameters such as growth performance, slaughter and blood parameters, and gut health. As long as the contaminants in its content are kept within reasonable limits, mixed feeds containing up to 10% crude glycerin can be used in broiler nutrition, but further studies are needed to determine more indices such as carcass performance, blood parameters, intestinal health.