The demand for food has increased dramatically as the global population increases, putting more strain on the sustainability of agriculture. To fulfill this requirement, it is imperative to develop brand-new technologies. The application potential of nanozymes in the plant and environmental sectors is progressively becoming apparent as a result of their effective enzymatic catalytic activity and the distinctive characteristics of nanomaterials, including size, specific surface area, optical properties, and thermal properties. Herein, we systematically analyze the catalytic mechanisms of nanozymes with different enzyme-mimetic activities and summarize their applications in improving crop yields by regulating ROS levels and enhancing stress resistance and detecting and removing hazardous pollutants. Finally, we thoroughly analyze the challenges faced by nanozymes regarding size, design, application, economy, and biosafety and look forward to their future development directions to better serve sustainable agriculture.