Water scarcity, often characterized by prolonged drought and erratic rainfall, severely limits lentil (Lens culinaris Medik.) production in dryland regions, posing a significant threat to food security. This factorial experiment, conducted using a randomized complete block design with the lentil cultivar 'Bilesavar', evaluated the individual and combined effects of Pseudomonas fluorescens seed inoculation and foliar spermidine application (0, 0.5, and 1 mM) on lentil's agronomic and physiological responses over two years (2023-2024) under dryland conditions in Sari, Iran. Both P. fluorescens inocula-tion and spermidine application, as well as their combination, significantly improved growth parameters, grain yield, leaf pigments, relative water content (RWC), and osmotic adjusters (proline content and carbohydrates) compared with the control. Furthermore, these treatments enhanced the activities of antioxidant enzymes (superoxide dismutase, catalase, and peroxidase) while reducing oxidative stress markers (malondialdehyde and hydrogen peroxide). Notably, inoculation with Pseudomonas fluorescens alone resulted in the most pronounced improvements across multiple traits, including plant height (39.3%), leaf area index (LAI) (140%), total chlorophyll content (64.5%), relative water content (30.4%), proline content (83%), antioxidant activities, averaged over two years, for CAT (503%), POD (151%), and SOD (45.25%), as well as grain yield (214%), compared with the control. The highest biological and grain yields were achieved with bacterial treatment without spermidine. While both treatments effectively mitigated stress, their combined use did not show additive or synergistic effects. Correlation analysis revealed that grain yield was positively associated with biological yield, number of seeds per plant, 100-seed weight, plant height, leaf area index, photosynthetic pigment, antioxidant enzyme activities, and osmotic adjusters. In contrast, harvest index and oxidative stress markers (MDA and H2O2) exhibited negative cor-relations with grain yield. In conclusion, P. fluorescens inoculation and spermidine foliar application improved lentil's physiological resilience and productivity under dryland conditions by reducing oxidative stress. Pseudomonas fluorescensinoculation is a cost-effective and promising sustainable strategy to improve lentil drought tolerance and yield.