Nowadays, Artificial lightare used aupplementary lighting to control plantgrowthrocesses under greenhouse. Recently, thelight-emitting diode(LED) technologyhas beeused to optimize crop production. LED may increase plant resistance to environmental stresses. Salinity as one of the most important environmental factors is limiting agricultural production in the world. Therefore, the objective of this study was to elucidate the effect of LEDs lights irradiation on morphological, physiological and biochemical responses of celery under the salt stress. A split plot factorial experiment based on randomized complete block design with three replications with 48 treatments was used. Treatments were included 6 environments as spectrum lights (red lights (100 %), blue (100%), a combination of red (70 %) plus blue (30 %), white (100%) LED, fluorescent light with an intensity of 300 ?Mol photons m ? 2 s ? 1 , and natural greenhouse light), four levels of salinity (0, 100, 200 and 300 mMol NaCl salt solutions) and two cultivars of celery (Giant Pascal and Tall Utah). Result showed that, as salinity level increased, K + content, activity of guaiacol peroxidase enzyme, carotenoids chlorophylls content, fresh and dry weight and essential oil yield decreased, while proline and Na + contents and ascorbate peroxidase activity increased. The concentration of Na + increased in roots and shoots under natural greenhouse light, but the lowest concentration of Na + was detected under the red and red-blue LED lights. Antioxidant enzymes activities increased under red-blue light while proline content was increased under blue light. Chlorophyll and carotenoids contents increased under red and blue monochromatic lights. Red light also increased K + content, shoot dry weight. Under the red and red-blue lights percent of essential oil showed a significantly increase. The highest K + content was detected in shoots under red light and 100 or 200 mM NaCl. The most of guaiacol peroxidase activity was observed at 100 and 200 mM NaCl under the red-blue light. While, catalaz and ascorbate peroxidase activityes were the highest at 0 mM NaCl under this treatment. The highest content of proline was measured under blue light and at 300 mM NaCl. Concentration of chlorophyll and carotenoids were highest at 300 mM NaCl under the blue light. Under the red light, the highest dry weight and essential oil content were detected at 0 and 100 mM NaCl. The percentage of essential oil content was the highest under red-blue light and 0 and 200 mM NaCl. Our results indicate that red and red-blue may enhance yield and essential oil content of celery under salinity and non-salinity conditions. Key words : thelight-emitting diode(LED) , salinity, celery, antioxidant enzymes, essential oil content, growth characteristics.