Abiotic stresses, such as drought, salinity, temperature extremes, and heavy metal contamination, pose significant challenges to plant growth, development, and yield, threatening food security and leading to economic losses. Reactive oxygen species (ROS) accumulation under stress conditions triggers oxidative damage, which plants counteract through enzymatic and nonenzymatic antioxidant mechanisms. Key enzymes such as superoxide dismutase, catalase, and ascorbate peroxidase, along with antioxidants such as ascorbate, glutathione, and tocopherols, play pivotal roles in detoxifying ROS and maintaining cellular homeostasis. Implementing strategic agronomic practices can significantly improve plant resilience, making them more able to withstand adverse conditions. The main challenge in improving plant tolerance is optimizing these practices to ensure effective and sustainable stress management. To effectively improve plant tolerance, agronomic interventions must consider soil health, nutrient management, and plant management techniques, ensuring that plants receive the necessary support to thrive under stressful conditions. Application of specific antioxidants can improve abiotic stress tolerance by mitigating oxidative damage. This chapter provides a comprehensive analysis of these mechanisms and practical guidelines for integrating antioxidant treatments with sustainable agronomic practices, offering insights into improving plant resilience and agricultural sustainability under diverse environmental conditions.