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Barley is the most salt tolerant cereal‚ and is grown in a wide range of climatic conditions. To improve the plant tolerance to salinity‚ expression analysis of genes involved in stress tolerance could be effective in identification and development of tolerant genotypes. In this study, for evaluation of salinity effect on expression of Hv TIP2;3 and Hv TIP4;1 genes (encoding channel proteins in the membrane) in roots of barley, three genotypes; Clipper (salt susceptible), Sahara3771 (salt tolerant) and advanced breeding line (a salt tolerant line derived from a cross between Kavir and Sahra cultivars) were planted under 0, 100 and 200 mM NaCl. To determine the expression differences of these genes, RNA was extracted from root samples harvested at 24 hours, 3 days and 3 weeks after applying salinity treatments and cDNA was generated. Analysis of variance revealed a significant difference among genotypes, salinity levels and sampling stages for Hv TIP2;3 and Hv TIP4;1 genes expression pattern, whereas genotype × salinity interaction for Hv TIP2;3and genotype × sampling stage interaction were significant for both of the studied genes. The expression of TIP 2;3 gene in the 100 mM NaCl was increased in salt susceptible genotype Clipper and decreased in tolerant genotypes compared with control. Mean comparison of genotype and sampling combination showed that the expression level of Hv TIP4;1 gene at 3 weeks after salinity stress was increased in Sahara and advanced breeding line and decreased in Clipper. According to the results‚ it was confirmed that these genes are affected by salinity stress‚ and effective utilization of this genes in the barley in order to increase salinity tolerance could lead to desirable results.