This review discusses the role of polyamines in plant abiotic stress tolerance. Early studies suggested that polyamines are involved in responses to environmental stresses, and recent genetic, transcriptomic, and metabolomic approaches have revealed their key functions in regulating stress tolerance. However, the precise molecular mechanisms by which polyamines control plant responses to stress stimuli remain largely unknown. Recent studies indicate that polyamine signaling is involved in direct interactions with various metabolic routes and hormonal cross-talks, particularly with abscisic acid (ABA). The review also discusses the integration of polyamines with other metabolic pathways, including reactive oxygen species (ROS) signaling, nitric oxide generation, ion channel activities, and Ca2+ homeostasis. The biosynthesis of polyamines, initiated with the formation of diamine putrescine (Put), is regulated by anabolic and catabolic processes, as well as conjugation to hydroxycinnamic acids. The review highlights the importance of polyamines in plant growth, development, and stress responses, and the potential for using polyamine-based strategies to develop stress-resistant crops.This review discusses the role of polyamines in plant abiotic stress tolerance. Early studies suggested that polyamines are involved in responses to environmental stresses, and recent genetic, transcriptomic, and metabolomic approaches have revealed their key functions in regulating stress tolerance. However, the precise molecular mechanisms by which polyamines control plant responses to stress stimuli remain largely unknown. Recent studies indicate that polyamine signaling is involved in direct interactions with various metabolic routes and hormonal cross-talks, particularly with abscisic acid (ABA). The review also discusses the integration of polyamines with other metabolic pathways, including reactive oxygen species (ROS) signaling, nitric oxide generation, ion channel activities, and Ca2+ homeostasis. The biosynthesis of polyamines, initiated with the formation of diamine putrescine (Put), is regulated by anabolic and catabolic processes, as well as conjugation to hydroxycinnamic acids. The review highlights the importance of polyamines in plant growth, development, and stress responses, and the potential for using polyamine-based strategies to develop stress-resistant crops.