Glycyrrhiza glabra L. (Licorice) belonges to the Fabaceae family, which considered one of the oldest and most widely used herbs around the world. Rhizomes and tap roots of licorice have secondary metabolites such as glycyrrhizin, flavonoids, phenolic compounds, saponoids. Ecological factors are the dominant factors affecting the secondary metabolites of the plants. Salt stress is a major abiotic stress of plants in many areas of the world due to increasing use of poor quality of water for irrigation and soil salinization. Under saline conditions, plants have to activate different physiological and biochemical mechanisms in order to cope with stress. This study was carried to evaluate the effects of different concentration of sodium chloride on some secondary metabolites in block design and with three replications. For this purpose, rhizomes of licorice collected from two regional growing (Fars and Khorasan razavi), in fall 2016. Rhizomes were cultivated (with a diameter of 1 cm and a length of 15 cm) in greenhouse conditions. after 11 months, the plants were treated with different concentrations of sodium chloride (0, 100, 200, 400, 600, 800 mM) for one month. Than, plants were harvested and assayed phenolic compounds, flavonoids and anthocyanins. Results showed that salinity stress lead to increase phenolic compounds, flavonoids and anthocyanin significantly. So that, with increasing concentracion of sodium chloride, the content of these secondary metabolites were elevated. Also, the contents of phenolic compounds, flavonoids and anthocyanin in rhizomes of Fars population were more than Khorassan razavi population. Although, Only the interaction between salinity and population was significant in flavonoids content. Therefore, the treatments of salinity (especially 800 mM NaCl) caused to increase some secondary metabolites. One of the most important features of phenolic compounds is antioxidant activity which is closely related to their chemical structure. In conclusion, licorice of Fars population, with increasing secondary metabolites in rhizomes cause to ameliorate salinity stress more than Khorassan razavi.

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