The application of nanomaterials and nanotechnology has a significant role to play in geo-environmental engineering due to its potential to revolutionize environmental remediation through sustainable structural measures. Nanomaterials exhibit noticeably unique characteristics like a large surface area, reactivity, and mechanical strength, resulting in enhanced performance in relation to traditionally usable materials, namely, cement, lime, and fly ash. The chapter focuses on numerous ways in which nanoparticles, metals and metal-based nanomaterials, carbon-based nanomaterials can considerably improve geotechnical properties such as permeability, strength, and compressibility by the way of altering their physical and chemical characteristics. This emerging technology also supports sustainable practices leading to substantial reduction of environmental impacts when compared with traditional structural practices associated with implementing long as well as short-term environmental remedial solutions through minimal carbon emissions. Furthermore, nanotechnology facilitates relatively better result-oriented effective solutions for geo-environmental challenges such as groundwater contamination reduction, and flood control structural measures including landfill liners. However, the application of nanomaterials warrants in-depth evaluation keeping specific consideration of their environmental impacts, safety, and long-term behavior. This chapter highlights the promising role of nanotechnology in transforming geo-environmental engineering, presenting innovative techniques, and future prospects that underline its importance in seeking durable and sustainable solutions to address the challenges of modern engineering projects.