The field of structural engineering is experiencing a profound transformation with the integration of nanomaterials, enabling the development of smarter, more resilient infrastructures. Conventional materials, while widely used, face limitations in durability, strength, and the need for continuous health monitoring. Nanomaterials such as carbon nanotubes, graphene, and titanium dioxide offer solutions by enhancing mechanical properties, boosting sustainability, and enabling real-time structural monitoring. These advanced materials not only increase the tensile strength of concrete but also provide self-cleaning surfaces and support the creation of self-healing structures. This chapter examines how nanomaterials such as carbon nanotubes, graphene, titanium oxide, nano-silica, nano-alumina, nano iron oxide, and nano clay, improve the mechanical, electrical, and thermal properties of structural materials. It explores the real-world applications of nanotechnology in the construction industry and discusses the challenges and future directions for integrating these technologies into structural engineering. Furthermore, the chapter investigates the role of nanomaterials in the context of Industry 4.0 and the era of Digital Twins. With the development of high-performance materials and advanced health monitoring systems, nanotechnology holds the potential to transform the construction industry, paving the way for more sustainable, intelligent, and resilient infrastructure.