Silicon (Si) plays an important role in providing beneficial effects on plant growth and yield, especially under stressful environments such as salinity. The objective of this work is to study the effects of a fertilizer based on silicon (Na(2)SiO(3)synthesized from Tunisian silica sand) on sea barley (Hordeum marinumHuds.) under salt stress. Due to its forage potentialities, this species presents a very interesting capacity for the rehabilitation of non-productive marginal areas. Forty-two-day-oldH. marinumplants were exposed to three concentrations of Na2SiO3(0, 1, or 2 mM) in the absence or presence of salt (0 or 150 mM NaCl). The examination of the growth parameters, water status, lipid peroxidation, photosynthetic gas exchange, photosynthetic pigment contents, and chlorophyll fluorescence proved that silicon is a great interest support for the remediation of the deleterious effects of salt stress. Therefore, our fertilizer can be considered as an effective solution to cope with salt stress and promote the development of marginal lands. Taking into consideration its high efficiency and its low production cost, this product can compete with other fertilizers.