The present study was conducted at two field experiments in a private farm at Gilbana Zone in Sinai, East Qantarah District, Ismailia Governorate, Egypt, during the two successive winter seasons 2015/2016 and 2016/2017. This investigation aimed to find out the effect of chemical nitrogen fertilizer levels (15, 30,45 and 60 kg N/fad.), barley seeding rate (40,60 and 80 kg/fad.) and nano- fertilizer application on yield and its components of barley. The spilt-spilt plot design as a form of the randomized complete block design with three replications was followed. Application of nano-fertilizer appeared to produce high values in No. of both spike lets and grains per spike as well as the heavy grains/spike, 1000- grain weight and, increased grain yield/fad. Seeding rate of 80 kg/fad. appeared to produce the highest value in each of number of spikes/m2 and grain yield/fad. Meanwhile, the seeding rate of 40 kg/fad. recorded the highest value in each of No. of both spike lets and grains per spike, weight of both grains/spike and 1000-grain . Nitrogen fertilization was very effective on all yield characteristics, so any increase in N levels was followed by a significant increase in each of No of spike lets/spike, grains/spike and spikes/m2, also increased weight of both grains/spike and 1000-grain weight and grain yield per fa. Conclusively, these results finally recommend sowing barley with dense seeding rate of 80 kg/fad. and application of 60 kg N/ fad. In addition to application of nano-fertilizer to maximize grain yield /fad. under the experimental site and other likely environmental conditions.