Grapevine (Vitis vinifera L.) is one of the world's most economically important fruit crops. However, in Mediterranean regions, vines are regularly exposed to drought, one of the most critical abiotic stress factors affecting viticulture. This study investigated, over six months, the effects of a bacterial consortium, composed of two strains of Pseudomonas ssp, on grapevines growth, its water content and cellular homeostasis under four levels of water regime (75%, 60%, 50%, and 40% of soil moisture). The applied strains showed good tolerance to drought stress (up to -0.85 MPa), and high production of exopolysaccharides (EPS) and 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase. The results showed that, under moderate (50%) and severe water stress (40%), the inoculated grapevines plants exhibited significant improvement in terms of growth parameters such as leaf number, trunk diameter, branch number, and root length. Furthermore, the inoculated plants were able to maintain high relative water content (RWC) which increased from 56.90 to 65.86% for 50% regime and from 43.57 to 53.09% for 40% regime. The membrane stability (MS) with MS index increased from 61.68 to 67.31% (for 50% regime) and from 47.98 to 59.86% (for 40% regime), while electrolyte leakage (EL) decreased from 56.81 to 52.27% (50%) and from 68.13 to 62.23% (40%) at 180 day post-treatment. This study evidenced that inoculation with the Pseudomonas bacterial consortium could constitute an effective agronomic approach for sustainable viticulture in arid and semi-arid regions.