Background: Plant growth, physiological and biochemical processes are severely affected by soil salinity. In the present study, toward investigating the interaction of antioxidants and salt stress in Lepidium sativum seedlings, two antioxidants (β-carotene and gallic acid) were sprayed on the plants. Results: The findings revealed that total dry and fresh weight were adversely affected by 25 mM NaCl salinity stress. Moreover, K+ content decreased while Na+ content increased significantly. The application of β-carotene and gallic acid significantly improved tolerance to salt stress by regulating ion uptake, reducing H2O2 and malondialdehyde (MDA) content, as well as increasing enzymatic antioxidant activity and phenolic, glutathione, and chlorophyll content. Conclusions: Our findings are indicative of β-carotene and gallic acid in the induction of salt tolerance in economically important crops.