Heavy metal (HM) contamination of soil and water poses a significant threat to agricultural productivity and crop quality. While some HMs are essential micronutrients, excessive concentrations are toxic. Plants have developed complex molecular and physiological mechanisms to tolerate and detoxify HMs, including the sequestration of HMs into vacuoles, the synthesis of metal-binding ligands like phytochelatins (PCs) and metallothioneins (MTs), and the activation of antioxidant systems. These mechanisms help mitigate oxidative stress, DNA damage, and other harmful effects of HMs. HMs can also have beneficial roles in plant growth, such as aiding in nutrient uptake and metabolic processes. However, their toxicity can lead to reduced photosynthesis, chlorosis, and impaired growth. Understanding the molecular responses of plants to HMs is crucial for developing strategies to manage HM pollution and improve agricultural sustainability. This review discusses the sources, occurrence, and agroecological impacts of HMs, as well as the molecular, biochemical, and metabolic responses of plants to HM stress. It also highlights the role of transporters in HM uptake and tolerance, and the importance of genetic and molecular approaches in understanding HM detoxification mechanisms. The review emphasizes the need for further research to develop effective strategies for managing HM pollution in agricultural systems.Heavy metal (HM) contamination of soil and water poses a significant threat to agricultural productivity and crop quality. While some HMs are essential micronutrients, excessive concentrations are toxic. Plants have developed complex molecular and physiological mechanisms to tolerate and detoxify HMs, including the sequestration of HMs into vacuoles, the synthesis of metal-binding ligands like phytochelatins (PCs) and metallothioneins (MTs), and the activation of antioxidant systems. These mechanisms help mitigate oxidative stress, DNA damage, and other harmful effects of HMs. HMs can also have beneficial roles in plant growth, such as aiding in nutrient uptake and metabolic processes. However, their toxicity can lead to reduced photosynthesis, chlorosis, and impaired growth. Understanding the molecular responses of plants to HMs is crucial for developing strategies to manage HM pollution and improve agricultural sustainability. This review discusses the sources, occurrence, and agroecological impacts of HMs, as well as the molecular, biochemical, and metabolic responses of plants to HM stress. It also highlights the role of transporters in HM uptake and tolerance, and the importance of genetic and molecular approaches in understanding HM detoxification mechanisms. The review emphasizes the need for further research to develop effective strategies for managing HM pollution in agricultural systems.