Nanomaterials and plant biostimulants are attracting significant attention for their potential applications in the agri-food sector. These efforts have mostly focused on the independent applicability of these two emerging fields to achieve improved agricultural outcomes. However, an even larger impact can be created if the emerging fields of nanotechnology and biostimulant technology are combined. This transdisciplinary review combines two diverse fields to highlight the potential role of nanotechnologies in advancing the impact of plant biostimulants for the sustainable production of high-quality food. The review first explains the key concepts of nanotechnology in a tutorial style to offer the agri-food research community an improved understanding of the potential of nanotechnology. The review then dives deeply into plant biostimulants which are substances or microorganisms or complex mixtures capable of improving plant nutrition and growth, directly influencing the aspects relevant to food quality, safety, and security. The review presents a convincing case that combining nanomaterials with biostimulants provides a promising sustainable answer against food insecurity for the near future. Sustainability is central to our discussions, which is exemplified by cases, such as the production of plant biostimulants from waste material, thus contributing to a circular economy. The review also identifies promising avenues to utilize nanotechnology for improving the value of biostimulants. Strategies such as nanoencapsulation are proposed to produce nano-biostimulants that could act synergistically to enhance food quality while offering a solution to the increasing challenge of food production while respecting the environment. Graphical Abstract