In this paper, the effect of NaCl on the activity of soluble (SPO) and wall bound peroxidases (IPO, CPO) as well as the level of lipid peroxidation in roots of two cultivars of wheat (Triticum aestivum L.) were studied. Two wheat cultivars, Mahooti and Alamoot were selected as salt-tolerant and salt-sensitive cultivars, respectively. The plants were treated with 300mM NaCl for 24, 48 and 96 hours. The content of lignin and the ratio of CWP/FW were studied during 96 hours of treatment as well. Salt treatment increased the rate of lipid peroxidation and enhanced the activity of wall bound peroxidases, particularly in roots of Mahooti. These phenomena were also associated with an increase in the content of lignin in the walls. The activity of soluble peroxidase was also stimulated which helps to more scavenging of peroxide radicals produced by NaCl treatment. Meanwhile, the results suggest that in salt-tolerant wheat cultivar, NaCl treatment accelerated aging process.