The necessity of early disease detection in a rapid and precise manner has emphasizes the significance of incorporating novel technologies into clinical practice. A new horizon in this detection is represented by nanomaterials-based gas sensors called nanosensor, providing real-time, non-invasive, painless, and straightforward diagnosis via exhaled breath analysis (EBA). Through EBA, nano-sensors enabled the detection of various essential diseases since some of their metabolic products are detectable and measurable in the different exhaled volatile organic compounds (VOC’s) of breath. This chapter will explore the intersection of nanotechnology and medical diagnostics, elucidating how the unique physicochemical properties of nanomaterials may detect trace biomarkers in exhaled breath. An extensive analysis of nanosensor performance and capabilities is given, with a focus on how well each kind of sensor from optical to mass-sensitive to electrical identifies disease-specific biomarker. Further, the chapter explores breath sensor platforms, covering wireless communication, multivariable sensing systems, and breath sample methods that are essential to participatory, personalized, predictive, and preventative medicine. It also addresses relevant issues including humidity interference, selectivity, and sensor validation, setting the stage for further developments. The present chapter also highlights the exciting prospects of nanosensor in healthcare by closely examining current studies on different exhaled VOC’s and investigating market opportunities. The goal of this integration of state-of-the-art research and clinical knowledge is to accelerate the creation of high-performance gas sensors, promote early disease detection, and improve patient care.