Salt stress is one of the most important factors that endanger plant growth and production all around the world. Application of compounds which increase plant resistance to salt stress obviously has significant importance in reduction of economic losses. One of these compounds is the biological alcohol called ethanolamine, and the present study aimed to understand the way by which ethanolamine exerts its protecting effect against salt stress. For this purpose, 4-week-old Nicotiana rustica plants which had been kept in MS medium were pretreated with ethanolamine and 2 days later they were transferred to MS medium supplemented with 200 mM NaCl for 3 weeks. The our results revealed that Nicotiana rustica plants pretreated with exogenous ethanolamine showed elevated level of TAL activity and anthocyanin content whereas PAL activity was decreased, and reduced level of MDA, total flavonoid and phenol content in plants under salt stress condition. According to these results, it can be suggested that ethanolamine exerts its protective effect by anthocyanin content increase.