This study was conducted to evaluate the effects of salinity stress on anatomical and physiological traits using five genotypes (4 tolerant and 1 sensitive) of Bromuss dantoniea usingsplit-plot design with randomized complete block layout under omM (control), 200mM and 350mM NaCl in 2014-2015 . . Anatomical and phisiologycal traits comprised, leaf hair density, leaf and paranchyma thickness, vascular bundel density, vascular bundel area, metaxylem width, phloem width, bulliform area, low and high epidermal layers, stomatal density, stomata area, root diameter, root pith, cortex thickness, exodermal and endodermal thickness RWC, ELWR, RWL, IWC, plant height and dry matter (DM). The result of analysis of variance showed that salinity stress significantly affected all the measured triats. Salinity stress caused significant decrease in leaf and paranchyma thickness, vascular bundel density, vascular bundel area, metaxylem width, phloem width, low and high epidermal layeras, stomata area, diameter root and pith, cortex thickness, shoot width, RWC, ELWR and IWC, plant height and DM while it led to significant increase in thehair density, bulliform area, stomatal density, exoderm and endoderm thickness, and RWL. There were significant differences among Bromus dantoniea genotypes for all of the triats. Under normal and higher level of salinity stress, positive and significant correlations were observed bet ween DM and plant height, hair density, leaf and paranchyma thickness, root diameter and cortex thickness. Negative correlations coefficients were obtained for DM with stomata area and with vascular bundle area. The results of principle component analysis (PCA) showed that the three first components justified 76/1 and 69 percent of total varation of DM in normal and high stress conditions, respectively. Biplot obtained from the PC1 and PC2, showedthat genotypes with highest first component (DM potential) and lowest secound component (rate of water loss) possessed greater salinity tolerance than other ones.Acording to stepwise regression analysis 69 precent of DM was explained by plant height, root diameter, leaf thickness and hair density under normal conditions and 65 percent of the varation justified by plant height, diameter root, hair density, stomata area and exoderm thickness under high stress conditions. The results of path-coefficieent analysis for DM as dependent variable and other traits as independent variables under normal and high stress conditions indicated that plant height the positive (r= 48 and r=42 respectively) direct effect of on the DM. There fore, it is concluded thar reduction of vascular bundles area, metaxylem width, phloem width and increase hair density, bulliform area, exodermal and endodermal thickness lead toadaptation to salinity stress and less dry matter loss. Keywords : salt stress, Bromus danthaniea , anatomy characters.