Barley (Hordeum vulgare L.) is one of the founder cereal crop, domesticated about 10.000 years ago in the Fertile Crescent from its wild relative Hordeum spontaneum. It is grown as commercial crop world-wide and produced for feed and malting. Malt is the second most important use of barley, which is used mostly in beer, but also in hard liquors, malted milk and flavorings in a variety of foods. One of the important management decisions for the malt barley producers is the amount of nitrogen fertilizer apply to the soil. High yield of good quality grain with appropriate protein content and kernel plumpness are the goal of barley growers. High amount of nitrogen fertilizer increases the protein contents in the grain as a result high protein content decreases the extract yield, results in turbid beer and slows down the start of germination, while a too low protein content results in a lower enzymatic activity and slow growth of yeast in brewery. So nitrogen fertilization strategies therefore, must be carefully tuned in order to balance some contradictory goals of maximum production with the need to achieve low N levels in grain.