Chitin is a kind of natural biopolymer with abundant reserves, which mainly comes from the exoskeleton of crustaceans and has good biocompatibility, reproducibility and biodegradability. Its micro-nano scale fiber not only retains the excellent characteristics of chitin, but also shows the advantages of high specific surface area, high mechanical properties and enhanced interface interaction. The gel prepared from chitin micro-nano fibers has the characteristics of antibacterial and low immunogenicity, so it has broad application prospects in the fields of tissue repair, drug sustained release, wound dressing, food preservation and flexible electronics. Although the application of chitin fiber-based gel materials has been widely reviewed, there is still a lack of systematic summary from the aspects of raw material extraction, micro-nano fiber preparation to gel construction, structure-performance relationship and key challenges in scale. In this paper, the extraction methods of chitin, the preparation strategies of micro/nano fibers and the gelation construction technology were systematically reviewed, and the application status of this kind of gel in biomedicine, food packaging, environmental adsorption, flexible electronics and tissue engineering was emphatically discussed, and its future development is prospected, so as to provide reference for the research and development of chitin micro/nano fiber-based gel materials.