One of the most brutal environmental constraints affecting the growth and yield in plants is soil salinity. In many parts of the world, it is considered as a non-biological stress after dryness. In addition, salinity stress can affect the growth and metabolism of plants in different ways. It causes high levels of sodium which, in effect, lead to such dysfunctions as adversely affecting the activity of enzymes, reducing photosynthesis, producing reactive oxygen, disrupting the membrane integrity, reducing growth, and causing osmotic potentials. In this regard, mycorrhizal fungi and growth-promoting bacteria are known to be significantly effective in plant stress tolerance. Aim of the study was to investigate the effect of mycorrhizal fungi and growth-stimulating bacteria on the improvement of salinity tolerance of apricot seedlings. The experiment design was 4×4 factorial experiemt in a completely randomized design with four replications. The first factor was the inocultation with two microorganiusms (Rhizophagus irregularies and Pseudomonas florescent) and second factor was the level of Nacl concentrations (0, 25, 50 and 75 µmol). Before the cultivation and during the salinity treatment, one month after salt stress treatment various physiological and morphological parameters were performed. Results showed that, under salinity stress, ion leaching rate and leaf proline concentration increased significantly. Also, use of biofertilizers significantly reduced the leaf ion leakage and leaf proline concentration compared to control (non-inoculated) plants. Furthermore, it was indicated that salinity stress increased the activity of antioxidant enzymes (catalases, ascorbate peroxidase, guaciole peroxidase and superoxide dismutase) in apricot leaves. In addition, biocides increased the activity of catalase, ascorbate peroxidase, guaiacol peroxidase and superoxide dismutase enzymes and leaf chlorophyll concentration in comparison with the control plants. Moreover, simultaneous use of fungi and growth-promoting bacteria was revealed to be effective in reducing ionic leakage, increasing proline concentration and activity of superoxide dismutase, guaiacol peroxidase and ascorbate peroxidase enzymes. As concluding remarks, simultaneous inoculation of fungi and bacteria reduced the oxidative damage caused by salinity in apricot, which was due to increase in the activity of leaf antioxidant enzymes. Keywords : Soil salinity, Salinity Stress, Apricot, Mycorrhizal fungi, growth-promoting bacteria