Cellulose is one of the abundant polymers commercially produced, with an annual output ranging between 75 and 100 billion tons. Cellulose-based nanosystems can be prepared by a variety of mechanical and chemical methods. The mechanical properties, anisotropic shape, high surface area, strength ability, renewability, low density, and biodegradability of the cellulose nanosystem make it a promising candidate for diverse applications. It has extensively been used in paper processing, paint, textile, pharmaceuticals, aerogels, sensors, and scaffolds for tissue regeneration. Cellulose nanosystems are currently explored in photonics, nanofilms, filters for oil separation, newer composite materials, jet fuel, aerospace, flexible optoelectronics, and medical devices. This chapter has discussed the current methodologies for synthesizing nanocellulose, its properties, and various applications. We desire to communicate the recent ongoing nanocellulose research, physicochemical properties, and potential futuristic applications. © Springer Nature Switzerland AG 2022.