Chitin, a biopolymer, has drawn a lot of interest as a flexible precursor for creating nanoparticles with various uses. Chitin is unique in that it is biocompatible, biodegradable, and non-toxic. These qualities have sparked research into chitin-based nanoparticles as potential solutions in diverse industries, including agriculture, medicine, and environmental remediation. The innate characteristics of chitin play a vital role in the development of its nanoparticles. The distinctive structure of chitin, which consists of N-acetylglucosamine units that are -(14)-linked, makes it a perfect scaffold for nanoparticle formation. Chitin-based nanoparticles have been created using a variety of synthesis techniques, including chemical, physical, and biological ones. These methods make it possible to precisely control the size, shape, and surface properties of nanoparticles, making it easier to design them for particular uses. Through cross-linking or grafting processes, chitin is frequently modified chemically to produce nanoparticles with improved functionality and durability. Biotechnological methods use chitin's enzymatic breakdown to create nanoparticles, matching with sustainable and environmentally beneficial practices. Chitin and supporting components interact dynamically in the complex processes driving chitin-based nanoparticle formation. Understanding synthesis pathways is crucial for accurate nanoparticle engineering since these interactions affect the form and characteristics of nanoparticles. Additionally, the extraordinary physicochemical properties of chitin-based nanoparticles, such as their large surface area, porosity, and potential for functionalization, expand the range of applications for these materials, including drug delivery, wound healing, agricultural formulations, and pollutant sequestration. This chapter provides a thorough insight into chitin-based nanoparticles’ properties, synthesis, characterization, and applications.