Researchers have increasingly focused on utilizing agricultural waste for a variety of applications. Products derived from lignocellulosic waste are nontoxic, biodegradable, eco-friendly, and cost-effective. Among these, sugarcane bagasse stands out as a significant source of agricultural waste. Cellulose, the primary component alongside lignin and hemicellulose, can be extracted from this biomass. Nanocrystalline cellulose (NCC) can be produced from waste material by removing lignin and hemicellulose. The extraction of cellulose can be achieved through chemical methods, enzymatic hydrolysis, and physical techniques. Green chemistry aspects and the sustainability of these techniques are discussed and compared in this review. Since biodegradable waste is often dumped in landfills or burned, repurposing it to produce valuable products can contribute to environmental protection. NCC has a wide range of applications across fields such as medicine, pharmaceuticals, agriculture, biomedicine, and electronics, and as a starting material for various products. This article provides a comprehensive review of the process of isolating NCC from agricultural waste, the various techniques used for its extraction, its properties, and its numerous applications.