In most crop species, stress usually inhibits seed germination, seedling growth and vigor, flowering and fruit set. Salinity is one of the major environmental factors limiting plant growth and productivity. It is estimated that about one-third of world’s cultivated land is affected by salinity. Salt stress has toxic effects on plants and lead to metabolic changes, like loss of chloroplast activity, decreased photosynthetic rate and increased photorespiration rate which then leads to an increased reactive oxygen species (ROS) production. High salinity affects plants in two main ways: high concentrations of salts in the soil disturb the capacity of roots to extract water, and high concentrations of salts within the plant itself can be toxic, resulting in an inhibition of many physiological and biochemical processes such as nutrient uptake and assimilation. This article is review and the aims of plant response to salt stress.