During growth and development， plants are frequently exposed to abiotic stresses， including salt， drought， and low-temperature stress， which lead to excessive production of reactive oxygen species （ROS）， triggering oxidative stress and subsequently causing damage to cells. As an important osmotic regulatory substance and non-enzymatic antioxidant， proline plays a crucial role in plant responses to oxidative stress induced by abiotic stresses. This article reviews the structural characteristics and antioxidant mechanisms of proline， and focuses on discussing its multiple protective roles in resisting oxidative stress induced by salt， drought， and low-temperature stress. Proline can directly scavenge reactive oxygen species through its unique cyclic structure and redox activity. It can also indirectly eliminate ROS by regulating the proline metabolic network—influencing its synthesis and degradation pathways， stabilizing the cellular membrane system， activating antioxidant enzyme systems， and synergizing with other antioxidants. Concurrently， exogenous proline application has been proven to effectively enhance plant antioxidant capacity and mitigate oxidative damage. This paper also conducts an outlook on the regulatory network of proline metabolism and the application protocols of exogenous proline， providing a theoretical basis for enhancing plants′ ability to resist oxidative stress through regulating proline metabolism， as well as for the improvement of crop stress resistance.