Wheat is  an important Egyptian grain crop. Nitrogen have a major influence on wheat the productivity. The goal of N management program should be supplying enough N to achieve maximum profit from the crop. But any N not used by the wheat crop is potentially  subjected  to  leaching,  which  pollutes groundwater and decreases the efficiency of N fertilization. The availability of Nitrogen affect by the soil properties, especially soil salinity, soil content of total calcium carbonate and particles size distribution of soil (soil texture). Also, some other important factors as soil-pH, soil organic matter content and cation exchange capacity of soil...etc. The aim of study to nitrogen critical  level limitation of wheat crop under loamy soil through each of different nitrogen levels and obtained the maximum yield of production. Field experiment was carried out in El-Gimmiza Agricultural Researches Station Farm during winter season of  2012-2013 in Loamy soil. The experimental design was randomized complete blocks. Grain and straw yield for wheat crop were determined, soil available nitrogen was determined after harvesting. The obtained result observed that wheat grain plus straw yield was low at N₁-treatment (5586 kg fed^-1) and the highest one was at N₃-treatment (7294 kg fed^-1). Nitrogen critical level for wheat grain yield was N₃-treatment (60 kg N fed^-1). So, the nitrogen critical level for what grain yield is N₃-treatment (60  kg fed^-1). From the field experiment, the nitrogen critical level limitation for wheat crop yield is 60 kg N fed^-1 under Egyptian environmental conditions for El-Gimmaza area such as soil moisture regime, soil temperature, biotic activity and soil pH.