Abstract <p>This study examines the physiological effects of <i>Bacillus subtilis</i> (<i>B. subtilis</i>) on licorice (<i>Glycyrrhiza uralensis</i> Fisch.) seedlings under drought stress, aiming to establish a scientific foundation for enhancing drought resistance and yield in licorice. The experiment comprised four treatment groups: control group (CK), drought group (D), drought + <i>B. subtilis</i> group (D + J), and control (Hoagland nutrient solution) + <i>B.&#xa0;subtilis</i> group (CK + J). Drought conditions were simulated using polyethylene glycol 6000. The study analyzed biomass, soluble sugar, starch, antioxidant enzyme activities, and photosynthetic parameters of licorice seedlings to evaluate the effects of <i>B. subtilis</i>. The results indicated that drought conditions inhibited licorice growth and photosynthesis, promoted starch accumulation, decreased root peroxidase (POD) and superoxide dismutase (SOD) activities, and enhanced leaf catalase (CAT) and SOD activities. Under drought stress, the application of <i>B. subtilis</i> significantly enhanced plant height, root-to-shoot ratio, and root fresh weight of licorice seedlings, elevated leaf CAT activity, and improved photosynthetic parameters, including net photosynthetic rate, stomatal conductance, maximum photochemical rate, actual quantum efficiency of photosystem II, electron transport rate, photochemical quenching coefficient, and non-radiative quenching coefficient. Thus, <i>B. subtilis</i> enhances drought resistance in licorice seedlings by regulating stomatal function, optimizing antioxidant defense systems, and improving light energy utilization efficiency.</p>