<p>Drought is one of abiotic stress that caused multiple severe consequences on plants by disrupting a variety of physiological and biochemical processes. Acetic acid is an important metabolite in plants and acts as a source of energy to preserve cellular energy in plants under abiotic conditions. So, a pot experiment was done to study the effects of acetic acid foliar spraying at 10,20,30mM on soybean plants irrigated either by 90% water field capacity (WFC) or undergo moderate drought stress at 60% WFC. Results show that drought stress at 60% WFC significantly decreased all measured growth parameters, all components of photosynthetic pigments, indole acetic acid, IAA, seed yield quantity and quality accompanied by significant increases in growth regulators (abcisic acid, jasmonoic acid), osmolytes, reactive oxygen species, malondialdehyde, antioxidant enzymes activity (superoxide dismutase; catalase; peroxidase), and non enzymatic antioxidant and free radical scavenging activity. Meanwhile, foliar application of acetic acid boosted the growth and productivity of soybean plants grown under either drought stress (60% WFC) or irrigated with adequate quantity of water (90% WFC). It is obvious that acetic acid specially at 20mM induced drought tolerance of soybean via inducing growth parameters, photosynthetic pigments, growth regulators, osmolytes, antioxidant enzymes activity, nutritive seed value, non enzymatic antioxidant, as well as scavenging ROS. It must be advised to apply acetic acid at 20 mM to induce drought tolerance of soybean plants.</p>