Copper (Cu) is an essential micronutrient for plant growth and development, playing a crucial role in various biochemical pathways and physiological processes. Despite its importance, the physiological significance of Cu uptake and compartmentalization in plants has been underestimated. Cu deficiency, often occurring in alkaline or organic-rich soils, can severely affect plant growth and productivity. Conversely, excessive Cu levels in soil can inhibit photosynthesis and induce oxidative stress, potentially posing health risks to humans through bioaccumulation in the food chain. Plants have evolved complex regulatory mechanisms to maintain Cu homeostasis, including the expression of Cu transporters, chaperones, and efflux proteins. This review provides a comprehensive overview of the functions and regulatory mechanisms of these Cu-related proteins in plants. It highlights the need for further research to enhance our understanding of Cu deficiency and stress responses in plants, which could lead to improved Cu utilization efficiency and tolerance in crops grown in challenging environments.Copper (Cu) is an essential micronutrient for plant growth and development, playing a crucial role in various biochemical pathways and physiological processes. Despite its importance, the physiological significance of Cu uptake and compartmentalization in plants has been underestimated. Cu deficiency, often occurring in alkaline or organic-rich soils, can severely affect plant growth and productivity. Conversely, excessive Cu levels in soil can inhibit photosynthesis and induce oxidative stress, potentially posing health risks to humans through bioaccumulation in the food chain. Plants have evolved complex regulatory mechanisms to maintain Cu homeostasis, including the expression of Cu transporters, chaperones, and efflux proteins. This review provides a comprehensive overview of the functions and regulatory mechanisms of these Cu-related proteins in plants. It highlights the need for further research to enhance our understanding of Cu deficiency and stress responses in plants, which could lead to improved Cu utilization efficiency and tolerance in crops grown in challenging environments.