Using of mineral fertilizers in agricultural production has resulted in serious problems in the soil. Many solutions were suggested such as using blue green algae (cyanobacteria). Nitrogen fixing cyanobacteria one of bacterial communities which play a vital role to fix nitrogen and increase the plant's ability to tolerate salinity. In this work 12 soils samples were collected from different salty sites in (Baltim, Elhamoul, El-Ryad and Seidy-Salem) at Kafr El-Sheikh Governorate. Selected soil samples were analysed physiochemically, Cyanobacterial samples were isolated, purified and identified microscopically based on morphological observation. The propagated cyanobacteria isolates were also tested for their biomass accumulation, nitrogen content and their biochemical composition, i.e., carbohydrates, polysaccharides, protein and pigments content. Four nitrogen fixing cyanobacteria isolated from different saline soil, namely Nostoc calcicola, Anabaenavariabilis, Nostoclinkia, and Nodularia herveyana. Nostoc calcicola produce the highest metabolic components, dry weight, chlorophyll a, carotene, intracellular nitrogen, carbohydrates, exopolysaccharides, and proteins (0.949 gL^-1, 3.083 mg mL^-1, 0.192 mg mL^-1, 3.363 mg g^-1, 29.7%, 0.198 mg ml^-1, and 25.85 mg g^-1) respectively, as compared with other isolates. These results deduced using Nostoc calcicolain many applications as fertilization, food, pharmaceutical and cosmetics industries.