Аннотация:Chitosan and composite fibers containing chitin nanofibrils have been developed for usein cosmetology. The tensile strength of the chitosan multifilaments is 160.6 19.0 MPa, and of thecomposite multifilaments containing chitin, nanofibrils are 198.0 18.4 MPa. Chitin nanofibrilsintroduced into the chitosan solution contribute to the creation of a new spatial arrangement ofchitosan chains and their denser packing. The studies carried out by optical, scanning electron, andatomic force microscopy has shown that the serum, consisting of a mixture of lactic acid and sodiumlactate, contains extended oriented structures—“liquid filaments”. It has been also shown that amixture of serum and composite fibers based on chitosan and chitin nanofibrils has mucoadhesive,film-forming properties. The introduction of composite fibers containing chitin nanofibrils into theserum promotes the reinforcing effect of liquid filaments, the lifting effect of the film. The obtainedcomposition can be used in cosmetology as a skin care product.