This study was conducted to evaluate biochemical changes induced by foliar application with proline (control, 20, 40 and 60 ppm) on barley plants (Giza123 and Giza126) under saline conditions (4557 and 8934 ppm) at Ras Sudr. Proline had a positive effect on growth, yield and biochemical components in barley cultivars. Giza123 was better than Giza126. With respect to free amino acids, data showed that thirty three acids were detected in two barley cultivars. The most abundant amino acids noticed were asparagine, proline, alanine, cystine, γ-aminobutyric and lysine. Also, proline treatments led to decrease of malondialdehyde content and quaternary ammonium compounds (glycinebetaine and choline) in barley plants compared with the control. On contrary, the accumulation of quaternary ammonium compounds took the reverse effect with salinity. Proline treatments had a positive effect on antioxidant enzymes under two salinity levels. In this regard, superoxide dismutase and catalase patterns revealed the presence of about five bands for the two barley cultivars under low and high salinity as well as it was increased in band intensity at all samples under high salinity compared with low salinity.Electrophoretic behavior of soluble proteins showed the presence of 12-23 bands with 18-229 kDa. Bands of molecular masses 20, 25, 37, 56, 72 and 149 kDa in two barley cultivars were absent in all proline treatments under low salinity level and accumulated with all doses of proline and control under high salinity level and thus can be used as biomarker to salt tolerance. We can benefit from current study in alleviate the adverse effects of saline stress on barley plants under Ras Sudr conditions, by activating the role of induced resistance using proline which had a positive effect on most of the biochemical components and barley grain yield.