The study was conducted in the fields of the Department of Agricultural Research / Nineveh during the season. (2023 - 2024). Research included two factors: first: nitrogen fertilizer (fertilized, non-fertilized). Second factor: barley varieties (Rehan, Samir, Amal). The study utilized a completely randomized block design. The global experimental system with three replicates was conducted at the end of the season . The data was analyzed using the SAS program on a computer, with different averages marked with different alphabets, and the results were as follows: The nitrogen fertilizer treatment demonstrated a significant improvement over the non-fertilized. The treatment focuses on average traits. (plant height, spike length, number of spikes m-2, weight of 1000 grains, and grain yield). The Samir barley variety was significantly superior to the rest of the varieties in terms of characteristics (plant height, 1000 grain weight, and grain yield). The interaction between nitrogen fertilizer treatment and the barley variety Samir demonstrated significant superiority in all studied traits. The aim of the research is to determine the response of the three best varieties to nitrogen fertilizer in terms of growth and productivity.