This study investigated the physiological and ecological effects of exogenous NO ease Zizyphus jujube seedlings under salinity stress, intended to further understand the NO improved plant resistance and provide theoretical basis for the NO application in green cultivation of Z. jujube. Through nutritional hydroponic cultivation, the effect of exogenous NO on the polyamine, glutathione antioxidant enzymatic system and chlorophyll fluorescence features of Z. jujube seedlings was analyzed under four treatments:control (T1), 0.1 mmol/L SNP (T2), 100 mmol/L NaCl (T3), 0.1 mmol/L SNP+100 mmol/L NaCl (T4). Results showed that the 100 mmol/L NaCl treatment inhibit the growth of Z. jujube seedling, but addition of NO significantly relieved the effect of NaCl stress. Exogenous NO significantly increased the amount of putrescine (Put), polyamines (PAs), spermine (Spm), and spermidine (Spd) under the stressed condition. In addition, NO also increased leaf reduced glutathione (GSH) content, glutathione reductase (GR) activity and GSH/GSSG ratio, but slightly decreased the oxidized glutathione (GSSG) content. Meanwhile, the glutathione-S-transferase activity, the ascorbic acid (ASA) content, and the ascorbic acid peroxidase (APX) activity was increased. At the same time, NO treatment significantly improved the leaf PSⅡ maximum photochemical efficiency (F_v/F_m), PSⅡ potential active competency (F_v/F_o), apparent photosynthetic electron transport rate (ETR), actual photochemical efficiency (ΦPSⅡ), and photochemical fluorescence quenching coefficient (qP), but decreased the photochemical fluorescence quenching coefficient (qN).Through increment of polyamine content, activity of antioxidant enzymes and the content of non-enzymatic antioxidants, and reduction of photo inhibition and insurance of rational use of light energy, the application of exogenous NO relieves the NaCl stress on inhibition of growth and improves the salt resistance of Z.jujube seedlings.