Saltbush shrubs are halophytic plants found in many regions of the world, they are promising as forage sources, but their chemical composition varies during the seasons of the year. This study was conducted in Assiut, Egypt to investigate the nutritive value and chemical composition of quail saltbush (Atriplex lentiformis) and old man saltbush (Atriplex nummularia) as affected by the seasonal variations. Composite samples of leaves and stems of each species were collected in the winter, spring, summer and autumn of 2013. The nutritive value and mineral contents of the tested plants varied considerably during the year. Leaves had relatively low concentrations of phosphorus (P) and high concentrations of sodium (Na), potassium (K), and chloride (Cl) during the summer season; however calcium (Ca) and magnesium (Mg) contents remained unaffected throughout the seasons. The crude protein in the leaves of A. nummularia and A. lentiformis was about 22 and 18%, while in the stems it was about 6.7 and 4.6% respectively. The tested saltbush plants are good as protein source during the winter. In that season of the year, the crude protein (CP) of the leaves of A. lentiformis and A. nummularia was increased by 32 and 26% respectively compared to the summer. The ash content of saltbush plants was increased by about 25% in the summer compared to the other seasons, while the moisture content remained unaffected during the winter, spring and autumn seasons and then declined by about 17% during the summer, this indicates that saltbush plants may be minimize their succulence moisture content during the summer to achieve osmotic adjustment.