Biosensor is an analytical device which incorporates a biologically active element with an appropriate physical transducer to generate a measurable signal proportional to the concentration of analyte in any type of sample. Integration of nanomaterials in these biosensors can make them much portable, more sensitive and more economical. Moreover, as the sensitivity of detection in nanomaterial-based biosensors is enhanced, probe material is required in extremely low concentration, and by tuning the surface property of the nanomaterials, these sensors can easily be employed for selective and specialized detection. An efficient detection system can help in management of many a problem of our modern-day life. A nanobiosensor can be used for early diagnosis of deadly diseases like cancer, and early detection of cancer can drastically reduce cancer-related mortality. It also can detect presence of microbial pathogens in our body, food, drinking water, and the atmosphere. Nanobiosensor-based precision farming has the promise to reduce the excess usage of toxic agrochemicals. These sensors can be used for smart food packaging which can instantly make the consumer aware of any spoiled food. This detection system is much suitable for effectively detecting environmental pollutants. In this chapter, several nanomaterial-based fabrication techniques and their applications in different facets of lives are discussed.