The delivery of functional biomolecules, including DNA, RNA, and proteins, into plants presents a unique opportunity to manipulate plant traits and address challenges related to global food security and environmental issues. However, the current methods of biomolecule delivery in plants face various limitations, such as dependence on specific plant species, low delivery efficiency, and complex procedures. In this context, nanocarriers have emerged as promising systems for biomolecule delivery, harnessing the power of chemistry and nanotechnology to overcome these limitations. They offer new possibilities for plant-related research and have the potential to revolutionize plant bioengineering. This review aims to provide a comprehensive overview of the current state of nanocarrier-mediated biomolecule delivery within plants. It highlights strategies to overcome the biological barriers encountered in plants and discusses the future directions for nanocarrier design and application, expanding the scope of plant bioengineering.