This book emphasizes the recent advances in carbohydrate polymer nanotechnologies, especially discusses the applications, limitations and drawbacks, revealing directions to carbohydrate polymer nanoparticles and their nanocomposites for further use in various applications. Carbohydrate polymers and natural materials which are environmentally benign over the synthetic polymers and display potential features such as low cost, wide availability, biocompatibility, biodegradability, physico-mechanical properties and easy functionalization. The carbohydrate polymers consists of significant functions groups, i.e., hydroxy, amine and carboxylic acid, these allows the functional modification and metal nanoparticle anchoring via chemical reaction and physico-chemical interactions, respectively; which results in the formation of sustainable materials with tunable features. In addition, the chapters in the book looks into the synthesis, functionalization and characterization of various carbohydrate polymers and their nanocomposites and its commercial applications such as pharmaceutical, environmental and energy production being conducted across the world. More specifically, it covers the application of carbohydrate polymer-based nanomaterials as sensors, drug delivery devises, nanomedicine, food packing, environmental remediation, fuel cells, hydrogen storage. The content of this book appeals to graduate students and researchers from the discipline of nano sciences, carbohydrate polymers, biotechnology, nanotechnology.