Copper based nanomaterials (Cu-NMs) are a promising tool for agriculture to increase plant productivity and resilience. Controlling the copper supply resulted in enhanced seed germination and vigorous seedling development and early stage growth. In addition, Cu-NMs also control abiotic stresses such as drought, salinity, and oxidative stress through enhanced antioxidant defense mechanisms and plant survival and yield. Potent antimicrobial properties were demonstrated, controlling plant diseases caused by bacteria, fungi, and viruses, and as a pesticide or fungicide, limiting the need for synthetic chemicals. In addition, Cu-NMs also enhanced soil microbial communities, creating an environment that is balanced and that contributes to long-term agricultural sustainability. However, environmental concerns include copper accumulation, potential toxicity, and soil microbial community disruption. The long-term effect of Cu-NMs on soil health, ecosystem balance, and food safety still needs further investigation. Sustainable practices and regulatory frameworks are therefore necessary for safe use in agriculture. The aim of this chapter is to provide an overview on environmental impacts of copper-based nanomaterials in agriculture.